The Terminator 4150 throttle body likely will not flow enough physical air for a 540 cubic inch engine. Typically without modification they flow in the 830 cfm range. You can get them to around 900cfm if you bevel the lower throttle bores, knife edge the butterflies and go to countersunk set screws on the butterfly shafts. I think you would be looking at the Sniper Stealth 4500.
There is also the new offering from FiTech that is making it's way to market, called the Nemesis.
https://www.subscribepage.com/fitech-nemesis-pre-order
4500 flange, 1600hp capable and designed specifically for large cid engines.
https://www.enginelabs.com/news/sema...o-big-engines/