The 750 Dominator is a good carb so don't ditch it. You can easily convert it to a 1050 Dominator by changing the boosters. Mark W. can do that trick for you and set the carb up with the new boosters. Depending on how old the carb is you might want new metering blocks also. The modern billet blocks make it easier to dial the carbs in.

I also did a rocker arm article with the 240 heads. You can find it on the Hot Rod website. The HS rocker arms will work just fine as will the Mancini ones or the ones from Hughes. I ended up with the T&D rocker arms on my engine but they are more expensive.