I took a look a your photo's and I can appreciate that stripping the car isn't something that you where looking forward to...I would ask you how much do you like the car, how long do you plan on keeping it and wouldn't you feel better knowing what underneath the paint...especially after your going to the time and trouble to paint it?
Look at it this way, it should cost you about $100 tops to strip the car with 80 Grit on a DA...You still need filler, you still need to weld in patch panels, you still need primer...and by spending the extra $100, your getting cheap insurance and you know what's underneath your paint. You mentioned it only had 1 paint job over top the original and the car is a 1977? That would make the substrate on the metal now 36 years old. I know I'd feel better with a new substrate to paint over top of and by investing $100 you can have that clean substrate and know that there isn't any more rust lurking underneath the old paint.
Just my thoughts and if I liked a car and I was going to paint it, I wouldn't hesitate to strip it.
Hope you get more responses.