Found a perfect donor

[Chevy nutcase]

I've been searching everyday for a cheap truck or one being parted out to no avail. A cheap parts truck anyone selling whole still wants $3000 around here and I was never keen on a whole truck I'd likely scrap for a few pieces. For my 66 c10 I want a rear dif from a 71 or 72 to convert to 5 lug and I was considering a square body power steering setup. Today I spied this 71 frame with the 5 lug rear and power steering that I can scoop up this weekend for 800. Only questions I have for the gurus here is will i still need an adapter plate for the steering box? I know the rear trailing arms are valuable if they aren't rotted and if I didn't want to lower my truck id keep the front disc setup but I think that might be easy to sell as well. Let me know what you guys think