The width isn't the problem with the 255's, it's the height. Same for the 245's. A 245/60/15 is about 26.5" tall. Usually you want to stay around 26" at the top end, especially if the car is lowered any. The 245's can be done with the right backspace but you might not like the ride height needed to pull it off. If you could find a lower profile tire in a 15" it would work, but there's really almost nothing in 245 or 255 with less than a 60 profile.
I run 275/40/17's on 17x9's with a 5" backspace on all 4 corners of my Challenger. They're 25.7" tall, and even lowered pretty significantly from stock those fit. But tire availability in the 15" rims pretty much kills running wide tires in the front with 15's. There are some competition tires out there, but pretty much nothing in DOT legal street tires.