I have ran into this, use a barrel rasp in a cordless drill to gradually.... open the inside of the post . I also have compressed the windshield frame in a vise , you'll need to use something like hard rubber or nylon blocks instead of wood in the vise jaws as the wood is too soft. Either way rasp or compress go a small amount at a time and rechecking as you go . I left you my phone number in a PM. Alan