I used these caps and JB Weld on the back of the shift tower. These 2 openings never had caps but the oil from the T 90 does leak there. Make sure not to obstruct the rails . After JB Weld dried I applied permatex #2 around the caps as well. Leak free shift tower.
Service and parts arrived in quick fashion. I learned it is easier to call them so I don't order the wrong parts. But the web site does help you get started.