[steely]

Welcome!
Throw up a pic of your car when you get a sec.

Its been a couple of years since I worked on my window motor, but from my notes I put the window half-way down, threw a block of wood in there, and used a 3/8 socket on the 2 or 3 motor hex head bolts. I think disconnecting the power plug while in the door was a bit of a challenge.

I think you can do it your way if you put a block of wood in there to prop up the window.
I do recall later deciding to remove the regulator anyway so I could fix the regulator spring pivot, and clean and lube the whole thing. I found that to be broken during the motor process.

I hope this helps.