STS vs. SLS steering rack?

I once replaced a rack on an '88 Grand Am, and when the parts store asked whether it was a GT or not, I said yes because I wanted higher-effort and quicker steering.  It bolted right in and was more fun to drive that way.

Is there a difference between 1994 SLS and STS racks?  I"m picking the car up Saturday and it comes with the factory service manual(s), which will be helpful.  The Grand Am rack was bolted to the firewall, but I believe the Caddy's is bolted to the subframe under the engine.

Any pitfalls I need to watch out for?  I've done a search and can't find any posts with installation quirks.

Thanks! 

Let sub-frame down far enough to get bolt out of intermediate shaft. before lowering sub-frame to take rack out. SLS was a STS with a softer ride.

Thanks, I just bought a Haynes manual that specifies loosening, but not completely removing rear subframe bolts.
 
I know the SLS had a softer ride, but I didn't know if the steering rack was different.  It was in a Grand Am GT vs the standard model.  Also, my old Camaro Z-28 is much quicker and higher-effort than a Berlinetta.
 
Thanks for the input.  It doesn't look like it'll be as big a job as I expected.

It will depend on how car was optioned, maybe... maybe not. With last 8 characters of vin dealer parts person should be able to tell you

I know, I thought it was impossible.  The rack is outside  behind the engine, and the steering shaft goes uphill into the passenger compartment.  But there it was, I had the right front wheel on a ramp so I could get under it to try and see where it was leaking, and there had been a puddle under the right side (now I think it was A/C condensate.)  I poured P/S fluid into the pump, and it all disappeared, but nothing on the ground.  What the....?  I opened the driver's door to shut it off, and there was oil on the carpet.  Great.  It was getting on the rubber sound deadener by the steering shaft hole somehow and running onto the top of the carpet.
 
I just wanted to be sure that it was the rack and not just a hose before I went and ordered a rack, and I still don't know.  Guess I'll have to get out the jackstands and REALLY get under it.

It is unlikely to be a hose, if hoses or their fitting are leaking fluid normally it will be under car not in the car. It is unusal for seal a top of rack to leak, but if p/steering fluid is getting on carpet it must be