JT that is why I suggested removing the shift linkage and try to engage reverse manually directly at the shaft. Hopefully it will work there. Since the side cover is off already you can check out the action of the cross shaft.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.