A couple of thoughts off the top of my head, have you tried removing the retainer, and taking a look at how the spring is anchored in the base, you may be able to feed threw like one coil and re-anchor it, if that looks like it won't work, the best bet may be to find some quality made retainers, they shouldn't cost very much, I'll check some of my bookmarks for a supplier, I have heard alot of complaints about the Classic 30's tubes being too exposed so spending a few bucks to protect them will be money well spent................