Inner drive cups for Traxxas CVDs

[tedo]

Hi, I also have been ovalizing my stock drive shafts, so after some researching, I ordered the traxxas cvds. I am running rpm true-tracks on the rear in the middle hole position. Do I need the longer inner drive cups that traxxas sells. Also running misc. 1/2 offset truggy wheels.

I just don't want these popping out because of the flex of the rpms...

Thanks guys,
Ted