I don't think you need a motor retainer. If I remember correctly, one comes in the kit.

I had zero problems with the build. The difficult part of the build was getting the details right. The Spin Rockets on the NC are very basic in shape so you have to sand to have them even come close to looking right. The kit provides launch lugs (1/4 in) so I recommend replacing them with buttons. Finally, the only other thing that comes to mind is you have to sand the inside of the NC to get the bulkhead to fit. Make sure you rough up the MM and the BT to accept the epoxy when you glue on the fins. The whole kit takes about 2 hrs. to build if you have all the tools...

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Bravo52
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Jerry Little
TRA #11767
Level 1