I'm looking into swapping an early model, Carbed 454 engine long block, into a van/truck that came with EFI. The Van/Truck it's going into broke the crankshaft, I'm pretty sure it did, the flywheel turns but dampner doesn't! I want to use the early model block/heads or just the block assembly and put it in the EFI engine. Is there a differance in the blocks? What do I need to swap and can it be done? I want to keep the EFI but use the older block assembly as I'm pretty sure the EFI block is trshed.  

I can't remember which other forum i answered your thread on, but the intake bolt pattern for early and late model big blocks was the same, so you'll have no trouble swapping your EFI over.  

If I understand what you are saying the block/heads are the same or will interchange? So I can rebuild the non EFI engine and relace the EFI engine with a non-EFI engine and use all the EFI stuff. I'm pretty sure the EFI block is trashed.