Just an FYI for anyone looking to put a hitch on a 2006 WRX wagon.
I got one from Curt Manufacturing. Fit perfectly. I had to remove two bolts on the fuel vapor canister and loosen the front bolt to let it droop out of the way. Then, remove two rear rubber exhaust hangers, remove passenger side tie down bracket, remove driver side exhaust hanger bracket. You have to notch the bumper cover about an inch to let it clear the hitch (can't see it unless are nearly down to ground level). Did that with a Dremel tool with a cut off wheel very easily. Lifted hitch into place and propped it up with a jack stand and bolted it up. Torqued the bolts to spec's (sent with hitch), and re-attached vapor canister. Start to finish, less than an hour.
Also, you don't have to use a spliced in pig tail setup. Hopkins makes (43855) pig tail that just plugs in. Subaru hides a plug under neath the passenger tail light. Open hatch. Remove spare cover and tray. Remove two snap buttons from the passenger side foam block under the passenger tail light and remove foam block. Follow wires into back corner and dig the plug out. Plug it in and replace parts. < 10 minutes.