[sick472]

That's a tough one, but the last gap to be set usually is.

I would remove the cowl vent and try to bring the fender in at the top (an maybe up) where the yellow lines are in the photo below. You can see where the cowl vent and door do not quite match up indicated by the red lines. This will likely cause and offset between the door and fender (at the Yellow Star, fender could end up more inward than the door). This approach relies on there being shims at the lower connection of the fender (right in front of the door and below the fender). If so, removing some shims there would cause the fender to bulge back out and correct the offset at the yellow star. If there a no shims below, shifting the lower part of the fender outward would move the center offset outward, but might also create an offset down low.

Then reinstall the cowl. If there are no shims under the front of the cowl...you cannot get it to move downward without bending the cowl tab so it would sit lower to help close the gap. If you could get the front of the cowl to shift over a bit at the green arrow (this would require bolting the passenger side down and applying some pressure to the center to flatten it out or not bolting it on passenger side and just increasing the gap on the other side before bolting it down). Consider bringing the rear down (bolt behind door at green star)...it might help close the cowl-to-fender gap a bit more, but would increase the gap at the red star.

You should not have to remove the hood to try this, but do not remove fender bolts entirely to be on the safe side. And remember that this may change how the hood fits when you go to close it for the first time.

I have worked hard on two builds to get the gaps as good as they can be and I usually end up chasing the worst of it to the least noticeable area. Both of these projects were basket cases made up of multiple vehicle parts and after market sheet metal. An all original project has a much better chance of fitting well.