5th wheel for Colorado/Canyon twins?

My 5th wheel hitch rails in my diesel full size truck are 42" long and they are for 22,000 lb hitch. Regardless, rails can be cut off the fit as they only need to go from one truck frame member across to the other frame member because that's what they are bolted to. New mounting holes can be easily drilled thru the rails as needed to line up with the holes in the "L" frame brackets or other brackets. So, no big deal putting a 5th wheel hitch in a Colorado or Canyon! Besides, some of the smaller 5th wheels are only 7' to 7-1/2' wide and mirrors to see behind legally would be OK and no different than an 8' wide on the full size truck and then there's the 8-1/2' (102") wide that are sold the towed behind a regular full size pickup too. DUH!