We replaced the entire streetside of our
'56 Safari - both inside & out as well as the exterior streetside of our '64 Globetrotter. It's not difficult at all...especially when we had Kip to teach us how to buck rivets for the outside!
The inside just uses pulled rivets, so with a pneumatic rivet gun it'll only take about a day to do the actual riveting - cutting/drilling from the old panels as templates will take another day or two. With a long weekend coming up you could probably get the whole thing done in three long days with some planning ahead.
The only thing that could be a problem with doing the entire interior would be the curved end caps - they are complex curves and not readily available "new". Without the equipment to form these, you will have to re-use your old ones - which will require stripping/polishing or painting. However, the straight lower panels are no sweat - if we wanted the look of an aluminum interior, I would certainly replace the panels rather than strip & polish the old ones - MUCH easier! And by the time you factor in stripper, time and polishing - it's probably not much more expensive to just replace them.
Shari