My interest in forward control Jeeps began in the fall of 2003.  At the time my only vehicle was my 2000 Jeep Wrangler.  I searched for a used cargo van preferably with four wheel drive that would serve as a tow vehicle and a daily driver whenever the Wrangler was torn apart.  At some point I saw a picture of a FC-170 and thought that converting one of those to a van body would be the coolest solution.   I discovered that Jeep made a handfull of vans for the Navy and USMC under the designation M-678 and M-679.  Through a Google search I found an ad in a military vehicles message board that was nearly two years old at the time and read something like the following:

Even though the ad was very old I replied that I was interested in the vans. I didn't get any reply so in February 2004 I purchased an original condition FC-170 locally for $500 with the intent of making the van body myself. No sooner had I began work on the pickup than I get a reply regarding the vans. Turns out they were still both for sale. Too bad I just bought a different FC. Over the next two months I got the pickup running and kept in touch with the owner of the vans. I sold the pickup to make room in the garage and bought the M-678.

The M-678 was 1100 miles away in Ballinger TX, so getting down there and back would prove to be expensive since I had no vehicle to tow it with. Luckily, the owner was willing to work with me, and agreed to keep it until October 12, 2004 when he had to be in Raton, NM for business. I met him there with a rental truck and trailer which was very good because it allowed me to rent the truck as a local move for a single day plus mileage.

Once home, getting the van in the garage turned out to be a little more difficult than initially anticipated. My FC-170 fit in the garage without any problem, so I figured the van would too right? Wrong. The front of the van is the same height as the pickup at 82 inches tall (the garage is 83 inches). The rear though is 87 inches high. In order to get the thing in the garage the wheels must be removed and the lug nuts places back on the studs to hold the brake drums in place. Then an anchor point has to be made so it can be winched into the garage (see pictures below).

Winching M-678 into garage nose first with 2000 TJ.	Snatch block bolted to engine hoist base and weighted with junk from garage.

Work on the M-678 started out with a test of the electrical system.  Two new batteries were installed and hooked in series.   I found the solenoid to make  a healthy click, but the motor did not turn over.  the switch for the wipers failed to turn them on, and after a bit of messing around with the switches, I found the following:

Most of the wiring in the Jeep is original.  The electrical connections are a water-resistant type with a tight fitting sleve and a small metal tag (tracer) crimped on with the circuit number stamped on it.  The insulation on every wire is almost totally rotted off and there are many naked sections of wire.  Replacement of all the old wire will be necessary before the Jeep can become roadworthy.

After removing and labeling most of the wires, focus shifted to the big 2cycle 3 cylinder Cerlist diesel.  Since it appeared that starting this engine would not be an easy task, the decision was made to replace it with something more reliable and powerful.  I started thinking about what I had and what I wanted.  Lots of power, speed, but It's got to be cheap and reliable.

Cheap rules out another type of Diesel, and I want to retain a manual transmission, so I came to the conclusion that a Chev 350 and any side shifted transmission mated to a Dana 300 or NP 205 followed by a Dana 60, 14 bolt, or Ford 9" rear would be the best way to go (the stock Dana 53 would have to be rebuilt anyway and .  A friend knew of someone selling a small block Chevy mated to a "Muncie" 4 speed in what was left of a '68 pickup.  I should have printed out the "How to ID a Muncie" rather than memorize it as I memorized it backwards.

The transmission turns out to be a Saginaw 4 speed.  It also turns out that the only cases you can adapt the Saginaw to are the Dana-18 and Dana-20, so the D-300 and NP 205 are out.  The straight-thru distribution of power in the Dana 20 is preferable as it doesn't require power to be routed thru all the gears in the case when in 2 high.  So there I have it:  Chev 350-Saginaw-Dana20-Ford 9 inch.

The installation of the Advance Adapters kit # 50-1000 Saginaw to Dana 18 / 20 is fairly simple.  The most difficult thing was working out some missing parts issues.  I bought the thing through Mile High Jeep Rebuilders and I paid for an extra bearing and bearing holder, but they were not in the box when I got home.  I had opened the box with the counter guys at the store to check if it was the correct unit, but some where along the way I came up short.  I don't know if the retainer and bearing were left on the counter or never in the box from Advance Adapters, but the guys at Mile High were great and came up with a new bearing and a used retainer from their massive parts collection.

I didn't have enough pictures taken of the Advance Adapters kit installation to give it its own page, so I'm just posting some of the major stages in its progress.  I can say that it all went together very well and aside from pressing the bearings in with a proper press, I had no problems with it.

A.A. 50-1000 Kit	Shaft Comparison	Installing output gear

Saginaw 4 speed	Dana 20

None of this can be installed before the Cerlist comes out, so a good deal of time was spent disconnecting all of the lines and wires running to or near the engine and removing the shift linkages and driveshafts, transfer case, transmission, crossmember, as well as the radiator and shroud.  The size of the engine require the engine to be dropped out from underneath the body so the front axle and right leaf spring were also removed.