The F-786A j-stringers were a bit too long and were interfering with alignment of the F-706 bulkhead and the forward top skin. I marked an estimated amount to trim, removed the stringers, and trimmed the forward end. Reinstalled the stringers and skin, checked the fit again, and repeated the process until I was satisfied with the fit and the stringers had clerance on the F-706 and the skin cleco'd on well.