1. Buick 350 frame plates
2. Buick 3.8 motor mounts
3. trans crossmember into TH400 position if not so equipped
3.5. driveshaft for TH350
4. Complete wiring diagram for both the 70 Elky and an 87 TR
5. Return Fuel line from the regulator
6. Electric EFI pump and tank (you can use a stocker with an external and route the return line back into a vent, go with an EFI retrofit tank from someone like Rock Valley Antique Auto with an internal pump, or a sumped pan with an external pump)
7. TTA vacuum block for power brakes
8. Adapters for using the GN powersteering pump with the Elky box
I believe that is the majority of the things you will need to get an LC2 into an A-body. This list is neither definative or exhaustive so be prepared for more you'd have to do. I don't know how the downpipe fits so that might be a custom something or another.
Hope this helps ya out,