I can be done check this out,
http://www.mar-k.com/54_bed_on_a_53_frame.html. I just bought a new bed from Mar-K I debated using a 64 bed for TWO years then realized the amount of work required to make it work was worth more than $1200.00 I just bought the new bed last month. You have to raise the floor or flatten your frame out (get rid of the hump). In addition, I am 98% sure the fender holes will not line up, plus I think there are bead rolls on the bed sides that will be visible on the outside when the smaller 1950 fenders are installed. I say fill that piggy bank and buy the right bed. I can't see cutting the frame, and by the time you modify your bed it's going to require new paint and fenders anyways. Like I said I thought about this for two years and there is no inexpensive way around it.
