I am removing the rearend of my '70 chevelle. I've never done this before and I am new to Chevelle's, always had Camaro's before. I read that there is some concern with getting the rearend back in properly(lined up?). What is the concern about? This is a 12 bolt and I am having 3.73 gears installed. The plan is to put the control arms back in just like they came out. Is there a proper way/order to put in or take out the upper and lower control arms? If I decide to install poly bushings should I be concerned about binding?

I believe the concern is in the re-installation. Make certain you don't tighten the bolts fully until the axle is all the way in and sitting in it's normal position with the weight of the car on it. THEN tighten all the bolts. No worries about the Poly, but you might want the polygraphite to avoid squeaks.

No worries about Poly in the Lower control arms... The binding is when you put Poly in the upper control arms...

I usually try to bolt the upper control arms to the housing first, loosely (because they are harder to get to), then work on lining up the lowers...