Narrowed Rear end questions

Thanks for the help. Yeah I'm mini-tubbing and moving the springs. That rearend width was from your 66 Dart, right? Would that be much different to my 73 Duster? Sorry if its a stupid question, Im a newb to A body's
Actually your wheel wells have a much bigger opening than my 66 Dart(I also have a 73 Dart Sport,but not minitubbed)I did alot of measuring and got help from members,before I had any cutting done.I,m running 15x12 rims with 29.5x12x15 Hoosier slicks,but is tight.Car hooks good now.LOL:thumblef: