Help me out here what exactly is TFS? What's the american name?
Of all the Isuzus out there I don't know of any of them that can't have 33" put under them with about a 3" suspension lift, unless we are talking about some of the newer rodeos 98 and up require a bit more trimming and a possible body lift to clear 33's.
But let us know what you have and someone will tell you what has to be done to clear 33's.
TFS is the code name of the pickup('88-'03) 4wd, TFR is the code name for the 2wd.
UCS is the code name for the Amigo/Rodeo 4wd(MU/Wizard) and I think the UCR is the name for 2wd's.
The Trooper/Bighorn is called UBS.