MSD 6al wiring

Didnt MSD offer a standalone rev limiter years ago? Have no idea if they still do. Probably obsolete since most ignitions have them built in now.
Hey, there is a 6C on ebay right now at a good price.
https://www.ebay.com/itm/Vintage-MS...638135?hash=item2f41c11e37:g:MMsAAOSwY3Vel6El