or just swap the valve springs. it's not like the heads even need to come off to do that either. it's a no brainer surely?
i mean, how much is a set of springs compared to a roller can setup? he already has a cam and lifters that were fine up to now so reuse them and swap the springs in the new heads. and accept that he made a mistake but it won't happen again. why make that mistake even more expensive than it needs to be?
neil.