Quick, probably dumb questions from a transmission novice
There was a "special tool" for that seal where you pull the levers and screw it on over the shaft that sticks out of the case, a cork screw type deal that bites into the lip of the seals and draws it out without having to pull the VB.
But yeah other than the park lock rod being a pain (especially when reinstalling) it isn't hard to pull the VB while in the car.
I have a /6 truck with a 727 that I have to change that seal on if I don't decide to convert to a 4 speed instead. That decision is what's holding me back on fixing the seal (I even have seals for that, here) but there's plenty of room on mine to change it in the truck.