The pre-Taco truck frame is rated as a 1 ton frame. The only differences between the 1-ton Toyota pickups and their 1/2 ton counterparts were heavier rated rear springs, and heavy duty steering linkages.

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