98 Legacy GT head gaskets

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If the car is at 149K should it be safe to say they have been replaced? I know two ways of checking is to see if any oil/coolant is weeping between the gaskets and smell the coolant to see if any oil/gas mix is in the bottle.

[Reason]

It's never safe to assume, I seen these go as low as 30kto as high as 175k. If you go to a Subaru dealer they can tell you if it's been to one of the dealers to have it replaced via VIN.