If you are running non-turbo, they will typically give some indication of age before they let go. With a Turbo, you could destroy a new engine as easily as an old one, so there is really no major advantage to a rebuild there either.
If compression is good, you are probably Ok to keep running it. It will probably start flooding and idling a little rough long before you have any actual failures.
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1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers)
1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic)
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