Car hard to start when HOT

hard livin will do that to a car lol.

anyways... sounds like you have two separate issues. first is the cooling system. please remember that the block water jacket is part of the "system" and is probably clogged to hell. someone could have even added to the problem with stopleak. before putting on any new parts you need to flush it with a cooling system cleaner of some type. then flush it again. maybe 3 times for luck. then put your new radiator and other parts on. you dont want a bunch of sediment in your new radiator do you? make sure you fill with 50/50- premix dont use tap water.

second issue. could be gas supply OR ignition related. if the vacuum advance hose is cracked or rotten it will have a hard time starting. you might not notice it cold because you are getting the extra boost of gas. when working properly, a mopar will click - fire over - vroom very fast in the morning... my 340 always did, it cranked for about half a second before firing. once warmed up it might take a second and a half.
if it's gas supply... you probably have sticking choke linkage and/or the carb needs a good cleaning & rebuild. after years and years it gets all varnished inside, and that stuff builds up on jets, float seats, in the orifices etc.

summary: check vaccum advance hose for cracks/replace. rebuild / clean carb. flush cooling system well before installing the new parts.

http://www.autozone.com/autozone/ac...ator-flush/_/N-262g?itemIdentifier=525741_0_0_