The rear wheel wells are often usually smaller as well, though depending on the life it has had the bed could have been replaced. Back in late '80's when the mini sport truck was cool, a common swap was to use the 4x4 bed and fenders when running wide tires.

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