Just my 2 cents worth here with some concerns I went through while having my stretch planned out. #1: Type of truck - this is your largest concern as the distance from the bumper to the rear of the cab will play a crucial part in length of box. My preference here was the class 8 Macks, they have a stubbier nose yet will accomodate the big motors, or a freightliner FLD112 - large frame capable of holding 10 and 11 liter engines yet a pretty stubby front end. Either one of these units will allow you the 96" sleeper with a 22' box. Stay away from the FRTL Classic, Large Pete, etc. unless you just want to show off and run around with a small box on it! I ended up with a FRTL FLD120 with the standard 72" sleeper, twin screw (big truck = 2 rear axles or no loads over, say 8,000 pounds, and I personally would always opt for twin screw over a lift or tag axle), 308" wheelbase, 24 foot box and a liftgate. Total length 39' 10" with the dumb dock plate sticking out the rear (roll-up door). #2: REALLY shop around on the frame stretch. I got mine done for $1,600.00 at a large-truck frame/repair/towing shop in Rochester, MN and it was perfect. I did a 3-axle alignment on the truck after running it for over 100,000 miles and it was spot-on! The other estimates ranged up to $6,600.00 for the same work. #3: Let the Frame shop calculate placement of the axles!! Don't try to second guess them. That thing of mine was so easy to predict load placement on that it just made me grin. Don't ever place the rears way back or way forward, it just doesn't work and can actually be downright dangerous. Hope this helps, everything went well on mine - but remember to do LOTS of pencil pushing and planning, mistakes could put you out of business or hurt someone on the road.