The process I hope to use is to swap out the beam, fit the current susp arms to it but with Lobro/bolt-on style hubs so as to allow Lobro/bolt-on driveshafts to fit at both ends.
I have drum brakes and they are fine but I have read somewhere that you can use drum back plates on disc style hubs by cutting off the caliper lugs.
The only other concern is whether the 7.5" diff is also longer so that the rear hanger has to be moved backward, which will be difficult in my car. If it's longer in the forwards direction that may be ok as I have plenty of slack in the prop shaft