Hello from IA

Welcome from Fredericksburg, VA. That is a very nice Dart.

As for your question about tires, 265's are going to be very, very tight on the rear with stock spring setup. About the biggest I have seen recommended was 245 (255 if you are lucky). Otherwise, you are at high risk of chewing up the fender lip and the springs on the inside.

Thank you so much! I really appreciate the help.

welcome from sunny california , had 245/55 on 9 x 14 on the rear of my dart years ago . ran 225/70 on 15 x 8's on my dart could have gone wider 245 or 255 / 60's maybe . but tires were very close to the springs .

Thank you so much! The pictures are very helpful!