904 rebuild

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I am currently 2 for 2 with 904s that have no forward gears after I rebuild them...LOL>...found a broken piece in one...and the second seems like the front pump seals are not sealing ...LOL....I need a transmission dyno....then I dropped a transbrake and broke a piece on the valve body.....have to box it up and set it back to get repaired...**** happens...

In 72ish....they changed the front servo...went bigger....nothing wrong with the older ones for a daily drivers...that PK35xxxxxx is where they changed....
I'm wondering for my power level just how far to go I'm not going to take it to the track or at least not yet lol. I don't know a lot about trans brakes. Is it worth it at my going to be power level?