Transplanting a stock/rebuilt 261 into a 37 chev and need info on radiators. Would like to hear from those who have had success in this project. Jury rigged a crossflow radiator for breakin but found using no pressure rad cap and 160 - 180 stats caused boilover. Switched to 7psi cap with 160 stat and no boilover. The 37 rad fill neck does not look like it will accomodate a pressurized cap. What to do ??? Thanks for the help.