Does anyone know of some online literature that would help me repair a B&L SZ4 scope? I can see, when I remove the right eyepiece, that one of the mirrors has come loose. I've started a partial disassembly (I have an exploded view) but I need some guidance before I go any further. I could sure use some help from an experienced refurbishing expert. I really don't have the $ to send it in for repair, besides I'm always looking for a challenge.