I attempted some research with conflicting results about whether 2002 Pantera 2-up had extended travel tunnel.

Yes, it has ETT, and that's why I don't think the skid will work in a 91 El Tigre. I believe that you can use some of the parts to increase the travel on the El T without having the 13 inches.
The other option is to put on an ETT tunnel. Tunnels are relatively cheap, and the difference would be remarkable.

My local dealer has put 121 ETT TSL skids in 94 and newer Cougars, EXTs, and ZRs. *He daid all he had to do was redrill the holes but didn't have to move any of the support plates. *We are planning on doing this to a 95EXT 580 once we find a skid and he gets us the patterns. *I don't know what the differences between 91 and 94 were though. *Hope this helps some.

yes it does that is why the seat is high off the ground unlike the older 2ups

I'm putting a '98 ett skid in an '86 phazer. *Just got my lightening-damaged computer back together so now I can finish all the CAD work (I was almost done modelling the entire skid) and figure out exactly how much trouble it is. *Only problem I've found so far (not a big deal) is that the phazer tunnel is about an inch skinnier, so the front arm of the cat skid has to be sawed skinnier. *Gotta replace the rear arm mounting brackets anyway, so I anticipate being able to just mount them each outward about a 1/2 inch.

I called AC dealer parts dept asking if 2002 pantera 2up had ETT. *First anwer was yes it does. *I asked to check to make sure, the answer I got then was it does not. *I looked at a 2000 Panther 2up. *Top of tunnel appears flat, not with an upwept angle towards the rear in the tunnel top (like my 98 zr600) which is what I am assuming is the extended travel tunnel. *Maybe I am incorrect in this assumption. *What I am trying to do is find out how much trouble it would be to put 2002 pantera 2up skid into 1991 EXT longtrack (convert to 2up). *I know I would have to relocate rear mounting plate at least. *Have attached 2002 pantera parts diagram showing flat tunnel top. *Thanks for any info, great forum!