Ken, I just got my new 2nd hand cheapo camera connected to the puter. Here is the back of a non-GSO (DSE 4.5") reflector:
http://members.optusnet.com.au/~jano...irrorhouse.jpg
It's one of the the simplest setups you could have. There are three nuts that do the pulling and three springs that do the pushing. The bolts are fixed to the mirror housing.