Compushift is a HGM Electronics product.
http://www.hgmelectronics.com/files/...09.preview.JPG http://www.hgmelectronics.com/files/...02.preview.JPG
I came across these units when following a link from MegaSquirt EFI controllers, they are offered as a means to control a stronger option for a slush box in the GM autos. I see that know they sell the kit for the ZF4HP-24 as well as Ford autos.
They allow you to program your own shift criteria, I think the drag boys like them.

