Just out of curiosity, why are those castings in the "Stay away" category? I don't think we'll do any kind of headswap on it; Any tuning we may or may not do on it will likely be relatively short term, as our "tentative" plan is to swap a Duramax into it at some point. Not sure which cone yet, but I'm hoping to find a good LBZ doaner truck to convert the whole truck over to newer stuff.