I have 3 stock intercoolers in the garage, and all three of them look identical. But 2 of them are id'd Garret AID P/N 492000-2 on a tag on top, one doesn't say garett but has AID P/N 492000-1 engraved on the top, and the one on my 87 GN is engraved GTSD P/N 492000-2x. Anyone have any idea what intercoolers I have?