340 vs 360 confirmation

It is a 1975 Dart Sport. I haven't put them in yet because it's further down the line, but I guess I should try so I can find the right seat track of I need to!
If you’re putting 75 seats in a 75 car then you should be good to go. Double check now to be sure though. It’s the inner track on the drivers side that changed to reflect the added hump in the floor for the cat.