Can anyone clear up for me the allowable margin of error in the measurement: wing tips to vertical stab? ie " If the distance on the left wing to stab is 33" and the right wing is 33-1/4" is that a big deal? Just wanna know now while it's still on the board. I appreciate your answer(s).

Unless this is a "Pattern" ship, you're OK. I like to see it exact, however, I doubt you'll notice it in the flight characteristics.

The measurements you gave are well within reason. I too like to get it as "exact" as possible, but the wing could probable be off by several inches and the plane would still fly. It would only trim at one speed though and inverted flight would be difficult. 1/4" isn't going to make a whole lot of difference until you're a good enough pilot to not ask this question.