Unfortunately I'd be pulling numbers from my a$$ if I tried to estimate this for you. It depends on the tools that you have, I have air tools, and the condition of your undercarriage, I live in NE, so mine has seen some uglyness.

I measured my changeover in days, not hours.

I almost guarantee that your rear lower control arm/shock bolt/bushing will be WELL frozen. From what I can tell this is VERY common, but again depends on what your car has seen. I actually had to cut my shock, but I was installing new ones anyway. I also needed to replace the bolt from the dealer, $15.

I'm really worried that I'll scare you with this stuff, but I'm trying to set the bar properly, based on my experience of course.

I will add the caveat that it was worth it for me.