Hey Mike,
I just finished doing a tune on my 3rd B-3 and the shrink tubing worked really well on that cheap plastic guide. Took a few minutes for the hairdryer to work, but once it started shrinking it shrunk up nice and tight. Prior to the shrink tubing the guide was very loose, now it's a nice tight fit.
That bead of epoxy idea doesn't sound half bad. I would think it would certainly give the guide more strength. I can't see any down side in giving it a try, I mean heck, it's only a $20 gun to begin with

which is the reason I like em cause if I screw up I didn't ruin a 200 or 300 gun.
I'm like you, I don't own a lathe (wouldn't know how to use one anyway) and I don't have any friends nearby that own one either. Wish I did. Oh well, guess I'll just have to move next door to Gene,,,, he just bought himself a lathe and a whole bunch of "stuff" to go with it. The other good thing about moving next to Gene would be being that close to his wall of guns

Jeff