I had a similar problem, and was able to partially resolve it using the following process...
1) remove the windshield.
2) Select dowel rod and a Forstner drill bit of the same size, I used 3/8" dowel and bit.
3) Drill out the header to a depth of about 1 1/2" (be careful on the ends, there is not much wood there!)
4) Mix up epoxy (I used JB Weld) and plug the hole with the dowel and an ample amount of JB Weld.
5) After this has cured, drill a pilot hole in the middle of the dowel to provide bite for the screws, be sure to use FLAT HEAD screws - I did find some Phillips head screws that were easier to tighten using a brace and bit.
6) I was able to gain the needed space to open and close my windshield with an original style gas lid, the reproduction lids would not allow the windshield to swing open all the way.
Most importantly, I think this is a two person job. I tried a number of times to put this together by myself, but I could not get every thing to line up properly. One person to hold the windshield in place, propped up on a box and it allowed me to maneuver the drill/brace & bit more easily.