I removed the smog pump on my 88 c1500 TBI 350 700r4 truck with one minor problem that took me awhile to figure out.
I left an idler installed that needed to be removed. It cause me to go through two belts in eight months before I figured it out. I had lifetime Gates belts and got one freebie though, but I knew it was my fault so I paid for the second one.
I use a belt from a '95 model, IIRC, which still had the same pulley arrangement, but due to OBD, it didn't need the air pump anymore.
My truck is an ECM truck, and it still seems to know something is amiss. After about 30 miles in a single trip I get a check engine light, but no performance issues.
The paper clip diagnostic tool always reveals an EGR problem, which is related to the smog system, but the EGR system is intact and has been replaced since....still get the nuiscance light.
No other real problems...Oh yeah, I did have to McGuyver my stainless fittings that go into the exhaust manifold. The thread pitch is extremely hard to locate hi-temp plugs to keep the exhaust in the manifold. I took the originals and sawed them off in a vise, flattened and folded the ends and stuck them back in. Only danger to this is ripping a knuckle...Maybe someone else here knows where to find plugs, cause I could sure use that info, or even the thread specs, because I am good friends with a machinist.
I can go snap a picture and get the belt part number tonight because I have to install a headlight anyway...