I have done the conversion and run standard size 15x7 Cragars with 235/60/15, but I had to do some trimming on the edge before I took it to paint so they would clear. I only took out a pie shape just enough for them to fit. .....
Rob what is the backspace of that 15x7 Crager? Usually they are 4.0 inches. That and the 235 wide tire will usually do you in with an un lipped fender.