Estes Gemini Titan #1978 Build, Part 2, Engine Mount

The engine mount tube is shorter than normal at 2 1/2" long. This is to fit the locking fin unit.

The instructions have you use the yellow spacing tube to set the engine block. The engine block is even with the end of the tube. It's easier to simply press the tube over the block on a smooth counter top.

After talking to Robb, we agreed to do a replaceable Kevlar mount.
A Q-tip tube was set into the centering rings. A wrap of electrical tape held in along the engine mount tube.

This model doesn't have an engine hook, it's not needed with the fin can locked on.
One of the centering rings has a half-round cutaway for a hook. It reminds me of the Bullpup kit. Estes was obviously standardizing kit parts giving you a notched ring whether you need it or not.
I put the notched ring at the top of the mount. I added a scrap piece of card stock to block the hole.