I am planning on Building a M715 with a Cummins 6BT 5.9l I have.

I will be buying the 715 shortly and I was wondering about parts issues. A friend has a J20 that is not running he said I could have for parts...but I am not sure if they are interchangable.

So I guess my question is....How similar are the 715's and J20's???

Thanks
James