beacon

It's not going to be a 261 V6 but an I6 - Inline. Great motor by the way. Congrats!! The wheelbase also dictates the series. 6100 is short-wheelbase (137"). That will measure 60" CA (back of Cab to rear Axle). 6400 is long-wheelbase (161") - 84 CA. I think that was your choices from 47-52 or 53. By 54 there was an even longer 6500. Again, checkout this site. Good luck and Have fun.

Professional Novice