RE: GB Extra 300
smithcreek Im glad that someone is having some luck reaching them.
I tried several times to reach that place and no such luck, I needed a glass cowling last year for a chimpmunk and nobody was home and when I tried again today and yesterday I got the same thing , Stan and I went way back to when he was in Riverside CA. I had bought several items from him and got to know him quite well over the phone. He told me that he used a Aircraft epoxy used by the Gov and thats why the very few or no bubbles I always got a quality product. Although I may have a few more bubbles with FGS stuff, there quality has been ok over the years but there cowlings are a little heavier than the ones from Stans., but I don't think there any stronger just a diff process in the making.
Thanks for the info i'll try them again the next time I need some glass parts.