I inherited a 1999 Legacy Outback with 2.5L EJ25 engine that had blown a head gasket. The heads (and on DOHC the camshafts) have been removed. I do not know which cam cap goes where (other than knowing which is on left or right head and Intake or exhaust cam). That still leave two possibilities for each of the inner caps. 

So here is the question. Is it critical that the caps are replaced in the same place they came off of? 

They must go back into the original locations as they're line bored to match the heads. They should have a stamping on the top of them, something like I3, E6, I4, E2 with an arrow pointing toward the front of the engine. The number is what cylinder they go to and the I means intake, E means exhaust for what cam they are matched to.

+1 What he said ^^^^^

Edited November 30, 20169 yr by Crazyeights