$.80 cents a pound, damn that is cheap for new stock. You shouldn't have any problem doing the whole thing for under $200, including consumables, undercoating and paint.

Have you done much body work, bondo and welding? Sectioning the bed is the quick and easy part, getting it to look clean will take probably as long/longer as fabricating the flatbed.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed