Estes Alien Invader #3003 Build, Part 3, Replaceable Kevlar Mount

The centering ring had an inside burr that prevented it from sliding over the blue engine mount tube. This was rolled off with the back end of a Sharpie pen.

Fitting this ring over the engine hook will be very tight. I filed a notch the width of the engine hook down the full length of the inside wall.

On the left is the notch for the engine hook relief.

The inset picture shows the notch for the replaceable Kevlar.
Installing a replaceable Kevlar in a BT-50 is tight but do able.

On the left is the 150 lb. Kevlar line slid through the filed notch.

On the right is the fit of the long ring over the engine hook.
Notice the blue tube end got a coat of medium CA glue.