I have attached two photos of the gap on my turtle deck, where my lid closes. It is about 5/8 inch wide and pretty even all the way across the trunk. I was going to fill it by welding a 1/2 inch bar stock in place but thought I better check to see if the gap is correct first.
The whole gap view:
Close up view:
Mine has about the same gap,.....don't worry about it, but if you must, just elonggate the bolt holes on the sides in the bottom panel and move it up a little.
I have a NOS 26-27 turtle deck and the lid fits almost perfectly with a narrow uniform gap on all 4 sides, almost a perfect fit.
Thanks Donald and Chester ! I looked to see if I could bring the bottom panel up and that can not be done because of the way it is made - reproduction or home made replacement tacked by welds in place inside. I will tig weld a 1/2 bar stock in place and spot weld it with my mig via small holes in bar stock. Then just fill the bar seam smooth with Kevlar bondo and the light weight filler to bring the gap closed. A quick 2 hour fix.