I'd try a Proform / Brawler "950" race carb w/ 1.45v x 1.75t simply because they're more affordable and more tuneable.
Liked that one so much I bought a second one of them for later tunnel ram use.
All it needs is the transfer slot holes tapped and restrictors/jets added.
Brawler also has a street carb marketed as an 850DP with electric choke, but the primary venturi measures out smaller than standard.
Bought a main body of one of those to build up later for my C body. Was surprised to see that. It seems like a sound idea.
hopefully get a chance to try it.
For an 850, the BG annular booster model I had was so much more responsive than the two regular 4781s that I had,
it killed them both so I sold them.