First off, this thread has no pics.
I know, I know... kinda lame, yes. But if you're anything like me it's damned near impossible to stop every ten minutes while you're doing something to document it. So, it is what it is.
I'm posting this mainly because I did a fair amount of research here on legacyGT before doing the swap and didn't find a straight answer, so I figured it was only right to post one.
So, let me get this out of the way:
Yes, it is possible to swap 2008 STI seats (driver and passenger) into a 2005 LegacyGT AND retain proper airbag functionality. It isn't easy, but it can be done. I know this because my brother and I did it today. Here's how:
**This process involves tampering with the vehicles SRS system!! You are totally doing this at your own risk and should not even consider attempting this unless you have good soldering skills, especially in regards to cutting/splicing**
This one is actually a breeze. As we all know, the four bolt holes line right up and you need to swap over the seatbelt latch from the old LGT seat onto the STI seat. Note that there is a small U shaped proximity switch integrated into the LGT seat that detects when the seat is far forward. If the seat is very forward, this switch will prevent the airbag from going off and potentially harming the driver. In my case, being 6'2", this isn't a concern. Just the same this switch needs to be connected to the SRS harness to avoid warning lights, so simply drill out the rivets that hold it to the LGT and zip-tie it underneath the STI seat somewhere out of harms way.
From there you'll need to splice the old LGT side airbag connector onto the STI side airbag wire harness. I am nearly certain that polarity doesn't matter with these wires since both are identical yellow insulated wire (no distinguishing marks, etc) and really, all they are there for is to fire off the small explosive charge in the airbag... so polarity shouldn't matter.
Once this is done, install the seat in its new home, hook up the seatbelt, proximity switch and airbag connectors and check for airbag warning lights, etc. If you've done everything properly you should see no warning lights.
Okay, this one is quite the piece of work. I'm not going to do a step-by-step here (cause there's a lot of steps), but basically if this sounds like its too much for you, don't even try, cause it's not easy! Thank god my brother is a factory trained tech who's taken seats apart before.... otherwise I wouldn't have been able to get it done.
Simple stuff to start: seatbelt latch and airbag harness connectors get swapped over, just like the drivers seat.
The rest ain't so simple.
The thing with the LGT and STI passenger seats is that the seat occupancy systems are completely different and totally incompatible. Plus, the bottom of the LGT seatbelt is bolted to the LGT seat frame, but there's no place for this on the STI seat frame. This necessitates swapping the LGT seat frame (or base) onto the STI seat... or should I say the STI seat back and upholstery onto the LGT seat base? Oh well, you get the idea.
In a nutshell, you need to remove the STI seat back from the base, then remove the seat cushion and upholstery from the base. Do the same to the LGT seat and then fanangle the STI seat cushion and upholstery onto the LGT seat base (using many zip ties in place of hog rings, not to mention cutting holes in the STI seat leather upholstery so that you can zip tie it to the LGT base). You'll then need to grind the mounting points of the STI seat back a bit to allow them to mount on the LGT seat base... Oh and you'll have to cut away some of the metal of the reclining lever to allow you to bolt the seatbelt onto the LGT seat base (since you're now using the STI seat reclining lever with the LGT seat base, you'll find that the lever nearly totally blocks the bolt hole for the passenger side seatbelt). Finally you'll have to modify the plastic trim around the reclining lever since again you're trying to mate the STI reclining lever with the LGT trim plastic.
With that done, plop that puppy in its new home hook it up, bolt it down and check for airbag lights. Hopefully you see none.
So yeah, it's a doosey... if you're doing both seats that is. If you wanna keep it simple, just do the driver's seat!
But the good news is that if you can manage to get it all together, it works! Just don't expect to re-use either of the LGT seats, they're both ruined now (one has no base and neither have airbag connectors).
Feel free to contact me with any questions, or just post them! Thanks