1986 emission removal

[kentrx1]

just purchased a 1986 custom c10 that is all stock.   has the 305 engine.  the vacuum lines are a mess with several broken lines.  the a.i.r. pump is physically connected, but no belt running on it and the vacuum line i believe to be going to the diverter valve is plugged.   runs ok, but would like to tidy things up and block off some of the vacuum lines that may or may not be leaking.  Any thoughts on removing the air pump and plugging exhaust holes with pipe plugs?  If so, what size plugs do I need?  

[SILVER SLED]

Get rid of that stuff. Get a set of shorty headers or older manifolds.  Don’t know what size plugs you’d need. 

[garagerog]

Years ago I removed the A.I.R. system on my 84 K20 HD camper special and I think I used 3/8" NPT plugs, but it's been so long ago I can't swear to it. The pickup is now on Kodiak Island, so I can't get a look at it.