I will be contacting you! The exhaust is going to be a challenge.
So I installed the mock up engine and TH400 tranny last night. Only minor tube work is required so the passenger coil packs can fit.
Advanced Adapters makes the engine mount kit that makes it so easy to install a LS motor. They also offer the correct flex plate and torque convertor bushing so we can run the very stout TH400 transmission. The engine mount kit moves the engine slightly to the passenger side making it easier to get the front drive shaft in place.