Go for it, When I built my MDT everyone thought I was Crazy also. Had a Chevy 1 ton crew cab dually w/454 Gas, that was modified, avg 8 MPG towing. Then I purchased a used GMC TopKick, 3116 Cat 6 speed added a 60-inch sleeper and a dually bed at that time, pulling a 38 foot TT, down through Tennessee, not as much strain on this truck, average 18-20 MPG. Now I have modified the bed to tow a 15,000 lb FW. Again, looking to upgrade to HDT single axle. Can purchase used for $20 to $25 K Vs $64 K for a Ford 550 w/unproven Diesel.
Well....when I was younger, I thought having too much power and wasting gas was a lot of fun....but I'm older now, and I KNOW too much power and wasting gas are definitely a lot of fun. It all depends on your view of what fun is, now doesn't it?