Ok I've got an 88 N/A. I'm running a custom 2.5" catback and a gutted main cat. I'll be installing a RB header and then running a straight pipe with a silencer to the catback.

So what do I do with the airpump connection?

 

Without cats on an 88 N/A the airpump now does nothing of value. This also make the Split Air Pipe, ACV, and EGR useless. These can all be removed, and blocked off where needed.

 

Stupid question.... how do I block them off?

 

You can order block-off plates, or just make your own. Just make them the same size as the flanges on the EGR, ACV, whatever else you are blocking off, then bolt them down just like you would the other pieces. Make sure you still use some type of sealant or gasket to prevent vacuum leaks.