Floor repair

[Slammed96]

I've been doing a lot of reading on replacing floors/rockers/cab corners on here lately and noticed that the vast majority of writeups involve having the cab off of the truck. Aside from the obvious ease of access and space, is there any disadvantages to doing these repairs with the cab on the frame? I'm limited on space, so it will be less hassle to leave the truck mostly assembled. I plan on going slow and doing one smaller section at a time so I don't have to worry as much about the cab flexing or tweaking.