I've replaced them before, you don't need to replace anything but the airbags on the OBDI Subarus, but I don't know about the OBDII as I haven't done any of those, just make sure your battery is dissconnected when you plug them in, and install both while the battery is un-hooked, once you have it all back together you can hook the battery up.....
have fun on that passenger side one
I just did them on a 95 Impreza.....driver's side is a piece of cake....the Passenger side is a real PITA....
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Huck
Subaru Ambassador
92 SVX LS-Tour Magnaflow Exhaust, 5-Spd-AWD
88 XT6 AWD 5-Speed "Bride of FrankenWedge"
15 Impreza Premium Sedan
15 Crosstrek XV 5-Speed
My 5-Speed "How-To" Write-up
1976 Pontiac Firebird Formula
Current Count of Subaru's Owned.... "70"