The GEM owner has a few more steps to perform than a fork-mount owner. The first task will be to install the "head" of the GEM, the mount on the already assembled tripod. How this will be done depends on the particular mount, but most use a variation of the threaded rod scheme used to attach Meade fork-mount scopes to their tripods. Follow the instructions in the manual and make sure the head is firmly attached since it will be supporting a fair amount of weight.
Once the GEM head is on the tripod, install the counterweightson the declination counterweight rod. Never, ever, place a telescope on a GEM without first installing these weights. Likewise, during disassembly, always remove a telescope from a GEM before removing the weights. Without weights to counterbalance the telescope load, even a firmly locked right ascension (RA) axis will come loose and slam the lovely new OTA into the tripod. That may cause the whole shebang to become unstable and come crashing to the ground. Attach the weights to the mount by unscrewing the "safety bolt" from the end of the counterweight shaft, sliding the weights up the rod and locking them in place with their setscrews. Be sure to screw the safety bolt back on after the weights are installed.
Once the mount is ready to go, the telescope tube can be installed. Most GEMs feature a dovetail-cradle arrangement. The tube will have a dovetail bar mounted on its underside that slides into the corresponding cradle/saddle on the mount. In some cases—the Vixen mounting system, for example—the dovetail can be "dropped" into the cradle; it will not have to slide in from an end. Before attempting to place the scope on the mount, be sure the cradle's retaining bolts (there should be at least two, often one large knob-headed bolt and one small safety screw) are loose. Then, holding the tube firmly, lower it onto the mount and into the saddle. Making sure it is completely seated, tighten the bolts while still holding the scope in place with one hand and cautiously let go. It might not be a bad idea to have a "spotter" assist the first time, especially if the scope uses the Losmandy dovetail system, which does require the scope to slide into the saddle from one end. When the OTA is firmly attached to the mount, proceed to install any permanently mounted accessories such as a finder scope or red-dot pointer.
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