When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
On my MY 98 WRX it was under the drivers side of the dash, just above the fuse box. It clipped in fairly high up though so you have to do some digging to get to it. Its round and silver on my model year.