I think cutting the frame is not so bad if it's done well, as it's not easily seen but i wouldn't cut the body on your car for bigger tyres.
Mick


69 Dart GTS 440 mopar .590 cam, Edelbrock heads, 3200#
best et 6.45, 106.78, 10.14, 132.88 mph, 1.47 60ft
best 60ft 1.36