I used the 318 and 904 trans, I wanted to go with the 4 spped the truck was setup for, but I changed my mind, I figured what the heck. I prefer manual trannys, but it was hooked up to the motor already, so in it went.
The hardest part was figuring out where the frame was going to be cut at. That took me two days of measuring and dummying up frame rails and getting it all fit, then trans fer to cardboard to trace it onto the frame rails of the 70. I was happy right aay with it, and went to town with a sawzall, no looking back now.
After I got it up in there and squared it, I was happy with it and tacked it in. It fit so nice all the way down each frame rail, I couldnt even slip a piece of paper through anywhere, all my plotting and measuring paid off.
after I had it all welded in I had to get a tranny crossmember for an auto, I bolted that in after I found one in my pile of parts, that took a while to find. I made an auto shifter next that used the four speed handle as a shifter, that looks so good in there, I bet I will fool almost every body with that. The diplomat driveshaft was the perfect length so I bolted that in. That was nice. I bolted the tranny tunnel back in and I had to find a gas pedal next. As it turns out, he robbed the pedal out of this truck and put it into the red 4 wheel drive I bought from him. So I had to look for a solid linkage pedal and I found one of those at the local junkyard. Got those swapped out and I then tackled the wiring of the 318 to the 70. It was a lean burn ignition motor, I got rid of all that and just wired in an HEI module and it fired right off for the first time. Apparantly that is why the car was taken to the junkyard, the lean burn was not working. I was kind of worried it might not run, but it runs real good. Next was a gas tank, bolted that in and ran some new hose for a fuel line, the steel one was awol, so I just ran rubber all the way to the front, new filter also. It sure is nice using up all these parts I have been holding onto all these years. I bolted the rad in out of the diplomat, but it was to close to the fan so I cut the brackets off the sides of the rad and just threw it in and put the hoses on and connected the tranny cooler lines. I made new brackets for the rad to bolt to the rad support, I just have to wled it to the rad. I have it bungee corded in right now, just a tempoary deal. I ran out of argon tonight or else it would have been in. I hooked up the brake lines in the front and decided I would try to see if the power booster would work out of the diploamt, if bolted right in, but I had to lengthen the brake pedal rod 2 3/4 inches, then it bolted in, but all I had to do was bend the firewall lip above the master cylinder a little bit and it cleared, I also had to knock out the 4 bolt holes that the booster needed, that was weird, it fit perfect, to think afte rall these years, soemthing like that had the same bolt spacing. Same thing with the driveshaft, that was perfect, and the frame rails mimicked the diplomat frame almost perfect too, I couldnt believe that.
Next was the alternator, the diplomat had ac and a smog pump, I did away with that and got pulleys off of a 75 dodge pickup and an alt bracket too, new belts and that was done, the wire harness went right to it nice, and I plugged in the voltage reg. started it up and 13.8 volts, not to bad, Im getting luckieras I go along.
The steering was the last thing to do, I had to order the ujoints for the steering to line up, I used a 3/4 by 3/4 and a 5/8 36 by 3/4 u joint. I measured the steering shaft on the box and came up with 5/8, I was confident I ordered the right one. It showed up today and I went over and tried to put it on, it wouldnt go. So I cut the orig couple in half, then welded the u joint to it, It was that or send it back to speedway and try to figure out what the deal was, or just use the stock coupler. It turned out pretty dang nice. My argon must of ran out right after that, as I needed to weld a nut to some tubing and it was all porosity, so I got lucky there. Here is the shaft I made.
After I got all that in, I cleaned all the tools off and decided I would take it for a spin around the shop. I did that and I heard a growling noise. I thought maybe it was coming from the rear end so I jacked tha back up and put it into gear, no noise, I figured I would let it run a while to get the gear lube warmed up, and I checked a couple other things while it was running.
Earlier today I stoppped and lined up the exhaust work to be done. Monday he thinks he can get to it. The car had three cats on it, so I pretty much will trade him those for the exhaust. That is nice.
I took it out on the highway and drove it, sure drives nice with that front end. I need to get some 1 1/2 wheel spacers for the front of the truck, it is too narrow looking, I havent ordered them yet, but I will. That is the only down side of the diplomat swap, but oh well, it was fun, and the spacers will get it back to normal again. I know some people dont like spacers, but I dont mind them. duallys have them from the factory, and you never hear anyone complain about that. And they are like 6", 1 1/2" is a spit in the bucket to that.
Hope you enjoyed my story of my pats couple weeks, it was a fun project. I was thinking of putting a turbo on it off of a laser I was given, but I dont think I will. After the exhaust is done, Im pulling the cam and getting it reground to a lopier profile, it is a roller cam engine, so you can do that I guess, only 100 dollars too. That will bring my totoal to under 500 dollars, sweet.
Here is how I pulled the k frame out of the diploamt, engine, trans, rad, exhaust and all.
Not very road worthy. 
