Hi Keith,
I wanted to say My CaveCritter as Lew Named it, Was a 1965 or so Cave 6" mount and OTA. I purchased it for $40 but it had no optics

I had an RV 6 Someone left outside in oxnard. The mount took the brunt of a few years of the beach. Rusted and busted!!! So I started to re build it then the cave showed up. It was to tempting so the optics from the Rv 6 ended up in the cave. The secondary holder and primary cell in the RV6 is better built than Cave, faster cooling, better finder, nicer to adjust the secondary. But the Cave OTA, Focuser (Sky micro) and mount are lightyears better than the RV-6 so it seemed like a match made in the heavens. After shortening the tube, Re mounting a few thing she snaped right into focus. All in all I have not been over whelmed with the quality of the primary mirror from the RV-6 but then again I am compairing it to some awsome optics that come around here!! The colimation process with this scope alway leaves me scratching my head a little which may mean the mirror figure is a little whacky... Anyway thats my experience with the Cave Critter. One other thing if you need parts for an RV 6 I have a few floating around...
(aveman