I think it comes down to what you want to spend. I had 2 sets of J heads and i think I mentioned this in another thread but, I sent the 1.88 set out in 2013 it cost high 400 and some change may as well say $500 dollars because I think it was 496 or something plus add the cost of the cores. Cant sell em for that, then this year I sent a 2.02 set of js out and that set needed more so it was high $600 and some change may as well say $700. I'm definitely not breaking even on that set but. They are good to go on an engine that will be low mileage cruised. Id take the chance ifand did to save some money also Id run some lead additive top cylinder lubricant etc. Maybe not every fill up but every other month or so. I think if it is a 70s truck or van id put the seats in but a 70s truck or van should already have them no?