Hey there. Unfortunately, most of the resources on this forum focus on the LTX platform from 1992-1997. However, some of us have a little 15+ LT1/LT4 experience.
My recommendation is if it's a max effort build, look into the Kong 2650 blower.
https://kongperformance.com/collecti...ce-lt4-tvs2650
BP Automotive makes some great standalone harnesses, but it sounds like you are going the Holley route. Have you given a thought to the fuel system yet? My brain is a bit hazy from when I owned my 18 ZL1, but I recall there being a low pressure side and high pressure side. You'll most definitely want to upgrade to hit big numbers as fuel seems to be the a big limiter on this platform (vs LS cars where you just throw a big pump(s) and injector at it and call it a day). Check this out:
https://www.vaporworx.com/resources/...-requirements/
I'd talk to Kong about a matching/common TB that pairs with his blower, either the 2650 or even a ported blower. There are a few out there that are common upgrades. I'm not up to snuff as to swap headers in a 4th gen, but I'm sure something exists. It would be a shame to go all out and be forced to run manifolds.
Motor mounts are a concern, but I think I saw swap plates on the ict billet website.
For cooling, I'd try to mimic a stock heat exchanger setup but essentially with an aftermarket hx. Like Afco. Or no hx and run an Interchiller setup, but not sure if that's a great idea on a track car since they are prone to condensation.
Meth, E85, converter, heads, cam, ported blower or 2650, fuel system, that should be at or near the 1000whp mark on the stock bottom end. Maybe more depending on the blower and how much boost you'll be pushing.