Help! Rebuilding by 66 dart but im putting in a slant 6 225 bored out to a 227

so I have a 1966 Dodge dart and the engine Im putting in it is a 1965 slant 6 225 bored out to a 227 and I’m missing a few of the parts. It was my dad‘s car and he unexpectedly passed away halfway through rebuilding it so I’m lucky I found the parts I was able to, but I’m missing my distributor and my push rods and my oil pan bolts as well as my headlight bezzels but right now I really need help figuring out what size bolt I need for my oil pan and i want to upgrade my distributor to an electronic one so if anyone knows the bolt size and has any recommendations for the distributor upgrade, please let me know!