The adapters can be found on Ebay from $50 -$175.00 all depends on time and the amount pf people needed them.Thank you. I did do some searches and I did find that bolt pattern are the same for 4/6bt as you stated. I guess I'm should clarify and that is where can one buy the adapter. I know I can hit some salvage yards but I was more interested in shops what will have these on hand. I'd called cummins south plain and they couldn't help.