LSX Swap questions

[RAB38]

I am in the process of putting together a swap in my 72 K5. I plan on buying the GM perf LSX 454 crate engine. I plan to mate it to my T-350 trans for a while. May change that to an overdrive down the road.

Questions.

1. What headers will fit best? Looking at hooker’s, schoenfeld, and headmans.
2. What flexplate do i need to mate to my TCI torque converter
3. What front drive accessory system works that is affordable? I would like to reuse my existing alternator, PS pump and my r4 AC compressor. If I cant then thats fine but I would think it should be possible. These are all part of the GM Performance Parts accessory drive kit i have on my 383 SBC.

Thanks