I have a 7/8" MC too and when first installed my brakes were not working. Issue was the pedal rod adjustment. I didn't have the rod long enough to account for the long pedal travel. I lengthened the rod and had amazing brakes. I would check that first.

I assume you have manual brakes too?

Yes they are manual

The pedal rod nearly bottoms out on the brake switch mounting area. I would presume it is long enough since I can't adjust it out any further.

I wouldn't assume that. I have a lot of pedal travel in my car...Can you pull the switch out and test to see if you get more brake by increasing the travel?

When I had my issues I was certain there was a huge issue with the brakes but it was all the rod.

Yep... I don't even like them for autocross either. They take way too long to react for my taste.

I can't make it any longer and still have the brake switch work properly.