Probably a Dumb Question

[ChevyC102007]

Ok so I have an 87 V-1500 GMC and it still has the original smog pump on the engine but it didnt have the cat. Asked my mechanic if I needed to put one back on since it had one (didnt know if PA regulations were like some other states IE WV where Im from originally) and he said no, so that leads to my question.
Ive been doing research on the site about removing it and so far I think I have a handle on the basics, the engine is a TBI 350 and from what Ive been reading I have to keep the O2 sensor. What Im wondering is there any other benefits to removing the smog pump and assorted "Rats" nest of pipes? (I mean besides the obvious of cleaning up the bay and having more room to work on things.)