having reread your post, i may have misled. on my carefree slide toppers i simply remove the end cap, roll the awning to the end, lock in place with a screwdriver in a convenient hole, notch the rail slot with a hacksaw, then slide everything out. havent tried it with the big main power awning, but except for the size and ease of handling, dont see why it would be any different.
it is actually harder to put back on, but i have found a trick to make it more manageable. i lay it out on the ground, fold in half, then roll it up towards the "pockets" with a pole or 1x1 in the middle (the full length of the awning) . this gives you something to hang-on to. on a long piece it also helps to have someone help hold the other end.
i dont know for sure, but doubt there are any cords, etc, in the area you would notch.
Bev & Dick and Fuzzy the cat
2005 Safari Cheetah 38
2009 Honda CRV dinghy