How many miles on the engine??? Might want to do a leakdown check on the engine (compression check at least!) All the top end goodies in the world won't do a bit of good if the bottom end is weak or tired.

Got to ask, why the thumper cam???? Probably not the best performance or economy for an engine that will be your daily driver.... I'd also have to suggest going to a hydraulic roller cam...Lots of problems the last few years with flat tappet cams as the Feds took all the good stuff out of the oil that prevents flat tappet cams from grinding the lobes flat.... Yeah, they're more expensive but a retrofit hydraulic roller properly match to the rest of your engine will give you better performance and not cause you a lot of grief (and additional expense) when the cam loses a lobe or two!!!!!

As for the pushrods, get a pushrod length checker then when the engine is al put together you'll be able to order the correct length pushrods for the engine....