Rear arm on VPI Classic 4 Turntable

Has anyone ever put a rear arm on a VPI Classic 4 turntable?  Does a 12 inch arm work comfortably at the back or is a 10 inch arm better?  What hardware is needed? How difficult is it to install - and use?

I’m a unipivot wand arm swapper.  I have 5 12 inch JMW 12 inch wand arms.  I was thinking of adding a 12 inch gimbal to the right sided arm but want to preserve a 12 inch unipivot for my other wandarms.

I am turning to the community for advice because try as I might I cannot get VPI to answer my emails or calls.  They seem to have abandoned customer service for some reason  I do love the turntable though despite being ghosted.

Useful input appreciated!