I don't know if it would fit on a 3rd gen 4Runner, but AFAIK it would bolt onto a 2nd gen. Couldn't say for sure if the rear valance would have to be trimmed, but on a pickup you have to cut notches to clear the mounting brackets.
'91 Pickup - Imelda
'08 Tacoma TRD - Donna
"Hey Macarena!" -- Thomas Jefferson