I understand your worries..
Believe me, if money was no object, i would do all the proper things that need to be done.
When you say I should have the crank fitted, what do you mean? Have the main bearings align honed to fit the "replacement" crank and have the crank installed profesionally?
Yup, I'd have the block and caps done to assure it is right, then whatever crank you use have it fitted to the block and caps. Or if your real good with plasti-gage(sp) have at it.