New guy to big block world, need a 400HP 383 Recipe

RPMs have angled plugs but they clear stock manifolds too. Stealths are straight plug. I think the MP "452" aluminum heads are straight plug too. Otherwise it's pretty much the same for everything. Have whatever heads you chose to buy gone through by a performance shop before you run them. I've never had an issue with distributors but some have. I think mainly with the MSD distributors that are larger diameter.