What have I got myself in to? Denver here we come!!

This thread inspired me also! Did mine a few months ago.
Sounds like you're wanting to do exactly what's in this post. I opted to install only the "required" items to make the engine/trans work and tie it into the original car gauges, a/c controls and power.

how did you plan for your game plan for parts?

My plan was to setup the engine on the stand with ALL of the accys bolted on, wiring run to ALL sensors. Once all the connectors had a home it was time to unbolt everything and install the engine. I did have to do 2 test fits of the engine.

If you had to do it again what would you have done different?
I'd have done it sooner!!!!!!!! oh, and plan wire layout a bit better. I thought it would sort itself out, but not so much. Some wires will have to be

The easy stuff:
1. Engine mounts are easy, engine-swaps.com BUT, your 318 mounts will work if I'm not mistaken
2. Suspension upgrades... at least stock v8 torsion bars, bigger is better though. Sway bars are a plus but not a necessity.
3. The 7.25 rear will explode... it's not IF, it's when and how bad. Think about 8.8 with discs in the rear...My 5.9L Duster will cook both tires when downshifting at 40-45mph
4. The stock Scamp A/C controls are easy to keep. All they need is vacuum to operate. Plumb them into the manifold,wire the scamp compressor wire to the new compressor + wire and ground the other one coming from the new compressor, have some new lines made to mate everything up and you're good to go.
5. Wiring the PCM is SUPER easy, it's like a stereo. One constant power, one switched power and one ground and it'll fire up. I spent weeks looking over the diagrams thinking it HAD to be more to it than that. There isn't, provided you have the right wires hooked up and didn't butcher the donor harness.

This is the "hard" section:
The hard stuff is keeping all of the electronics to go with the cruise control ( and anything else you want to bring over ) and grafting them into the scamp harness.
Get a FSM for the donor, this is a MUST. You should be able to find it out on the internet in PDF format.
Some things are easier than others to graft in. The cruise control uses speed sensors on the wheels or rear end and ABS computer....starting to see why it's not in the "easy" section? :lol:
I removed ALL of the extra wire from the Dakota harness including abs, lights, cruise control etc. Once that was done, it's plug and play.
*****KEEP THE ODBII connector*** I removed mine by mistake :banghead:

The cross member isn't really hard to do, but takes some time fitting a heavy transmission, cutting and welding, thus in the hard section. There is a nice sticky on how to install the fat a-518 trans.

The exhaust manifolds are also a sticky point. You'll need to use the 340 manifold on the drivers side, high $$ headers or restrictive smogger manifolds due to the power steering.

If you don't want to mod the battery tray, find a power steering pump bracket from a van, it moves the pump low enough to clear the tray.

Wiring the engine bay power distribution box is pretty straight forward as long as you can read a wiring diagram. I put this in the hard section because even if you can read and understand the diagrams, there are TONS of wires that you have to deal with. I removed more wire from the truck harness than was in the whole car to begin with.

Tips:
1. Keep as many of the harness connectors as possible. Even if you are going to completely remove that function. You might be able to reuse them for other things if you're careful with un-pinning them.
2. Bypass the ammeter now if you haven't done so already.
3. Be careful with the crank position sensor and dizzy when installing.
4. If you are removing functionality from the power distribution block, use the relay slots for headlights, cooling fans and other cool things.

Good to know:
The PCM switches ground to turn stuff on. Meaning, the device, sensor or relay will always have power and when the PCM wants to turn something on, it provides a ground. This keeps power away from the PCM and keeps the power distribution centralized....thus the power distribution block.
The PDC ( power distribution center ) is also has a portion that provides a central ground.

I love the car after the swap. I should have done it years ago. I'm still not driving my car on a daily basis, but only because I decided that the engine swap was more fun than the bodywork and it's 12 shades of primer.