[Jonboy]

This is just my $.02, so take it for what it is worth. Swapping all of that stuff over to the '87 is pretty ambitious. I personally like the original stuff better; it is what makes a square a square to me. I understand reusing the factory harness and all. That is one area of my swap I bit the bullet and bought a stand alone harness. plastic connectors that have been subject to 15 years of heat cycles are bound to be weak, and I didn't want to deal with the hassles. You can use the dual tanks you have, just upgrade the pumps and the switching valve, and you should be golden. IIRC, you already have the electric cluster. That will read the VSS output from the later model PCM- another problem solved. The 4L60E and 700R4 should be the same length, so use your transfer case as a starting point for the mounts and work your way forward.

This is just how I would do it- your mileage may vary.