in a 70 Coronet R/T....my car leaks so much power steering fluid out of this seal that it feels like I have to put as much oil in it as fuel in the tank.

I've got the column unbolted and pulled back, I've read the write up on FBBO forums, but I don't have a mini right angle pneumatic drill like the poster there used to put a few holes in it for drywall screws. This is a power brake car, and I'm not entirely opposed to pulling the brake master cylinder off, I'd rather not have to go thru the process of bleeding the brakes which otherwise work great.

any tips, suggestions, or advice?

If you can poke a few holes with a very sharp object like an Awl, Small center punch etc. you can then use thos to pry the seal out. Do be carful not to score the shaft or housing.
I do believe years ago I heard of being able to momentarily pinch or block the return hose to "blow" the lower seal out, not sure that would work though.
Might just drop the box so you have open access. Someone else may chime in as well

you should have enough slack in the brake lines to carefully remove the master and move it over some without having to disconnect the lines, depending upon if the lines are not "fiddle string tight" to any junction block.

I moved the master cylinder, then applied more hate & foul language and managed to remove it. There's no *simple* or *easy* way to remove it with the steering gear in the vehicle.

Perfect!

There is if you have the right tool. C-3638

well, at least it's out now.