Hard Starting

[1980 Chevy]

I have a 1980 Silverado with a 454 and Holley 750 carb. After almost two years of sitting, I finally got it going again after putting in a new motor. It's been running great for the past two weeks...when it's warm. But starting in the morning is difficult. Crank and crank and crank...nothing... .I think it may be choke problems. My wife says when it starts for her, she lets it sit for 2 or 3 min letting it warm up.....So I could get a manual choke...or replace the old carb with a new one. Any thoughts? Thanks!