My Dart Swinger Project!

Man buddy, I wish I was there to give you a hand
I always use a "known good working" carb for break in. Even if you have to borrow one.
coolant and tranny leaks can all be fixed
I don't think your valve springs and cam are so aggressive that you have to worry about the cam being hurt. I've had trouble on start ups before with new cam and lifters, I've never lost a cam