I'm in the process of buttoning up a 331 build for my 69. Kept it simple while taking advantage of some new tech, particularly converting the early model block over to accept a roller cam and adding a set of Brodix 5.0R aluminum heads and a Holley Sniper FI setup. Couple that with a stout Eagle rotating assembly, Weisco pistons and a REALLY good machine shop it should be a bullet proof little engine.