I do not see any reason you could not switch them one at a time. Just place a rage or something under the corner you are working on and prop/ tie the hood up with something like you said. I did a lot of things on my car that probably should of used two people.

The only trick I know of is for the installing the springs. I pushed fender washers in between each twist, alternating sides until it was stretched enough to place on the hinge, than pulled them out one at a time when in place. Made it really easy to install.

Oh, and did you buy re-pops or GM's? They are still available you know.