I have a 1 ton Chevvy that I bought as a chassis/cab, I then had an
alumin flat put on it.
I don't remember by how much, but the track on the GM is narrower than
the Dodge or Ford, which lessens the issue of wide butt. Steel flats
are around $800 here and when there are upfit allowances you can get
ALL that back from the manufacturers.
I really LIKE the flat, for me it is MUCH better than having to deal
with the narrow bed between wheel arches, etc. Sure its higher, but I
can load/unload from the sides.
On tolls (in New England) I pay the 3 axle rate, so that adds 50c on
the RARE occasion that I go through a toll gate. In Mass I was able
to register it at car rates, though it seems there is a difference ofo
pinion between (some of) the local police and the state registry on
this (-: I think the key is whether you're using it for commercial
purposes.