I have never tried 295 60 15 tires, but I do have 305 50 15 at the moment-soon to be replaced by 295 50 15. The 305 are just a tad too large, they have a 12.4 sect. width and are 27.1 dia. plenty of room upstairs, but just too close on the in and out sides. I do have the lips rolled for side clearance.
Good luck.
ps. Tires are on an 87 gn.