I have run into this problem many times over the years, as there are many different body makers out there, if you already have your posts and windshield frame, bolt that complete assembly together, (first!!!) then WAX the inside of the posts real good, this keeps the glass from sticking to the posts) then grind the corners of the body with a course (16 open coat disk) on your hand sander/grinder to get a good bonding surface, I even drill several small holes (1/4") in the area then build up the corner with fiber glass resin and MAT, now before this gets a chance to set up, slowly press the wind shield frame assembly onto the body at the angle you wish to end up with, you may use a long length of racer tape to hold the top of the frame in position until the glass goes off... then unbolt the posts from the frame and pull them off the body, you can now (if needed) ad some tiger hair or ground up mat and resin? or whatever type of filler you like, and again reset the posts back on and bolt the frame back to the posts, this will make a perfect fit and it will also take the strain off the small mounting bolts when finished, because the body now fits in the posts real tight...