What to with a fresh rebuilt motor that has been sitting 3 years?

I vote for Marvel Mystery over PJ Blaster, Marvel is ATF, lubricant, with spearmint oil which is a super penetrate, great at loosening things up without getting runny and going past rings. PB is more formulated to break rust loose not lube good metal. If its rusty, you are screwed anyway. Marvel will break loose and lube, PB only breaks loose. For a great demo, use it at the drill press instead of cutting oil. PB sucks and Marvel works great. Not bashing PB, use it all the time, just on outside of engine and on bolts its amazing. You can actually dump Marvel in carb off running engine and break loose carbon on used engines, break loose stuck rings. Used to use it on Rotary engine that were carbon locked all the time. :soapbox: just my $.02