Cliff has what you need.
https://cliffshighperformance.com/Qu...ottom-plug-kit
A test to see if they are indeed leaking is get it nice and hot and then park it for one hour and then start it. If it fires off right away then they aren't leaking. THe carb body has to get real hot to make them leak.
THere's only one accurate way to confirm your timing marks are correct. With a piston stop.
Like in here.
http://www.crankshaftcoalition.com/w...op_dead_center