Best way to remove EGR pipe off a 94?
 

And where can i get a blocking plate? thanks.

luckily i never had to. I hear just effort gets it off.

I remember it was hard to get out, but I think you just have to figure out the one way to snake it through. IIRC, I pulled it out in the intake side. I made my own blocking plate it about 5 mins with scrap steel, but FM sells one too.
http://www.flyinmiata.com/Store/images/04-70000.jpg

Sorry to threadjack a little, but besides the recirculation of some hot exhaust into the intake, is there any other bad thing about having the EGR intact? I was thinking about removing the piping as well on my '95, but haven't seen the pros and cons yet.

I only removed mine because it wouldn't fit into my BEGi manifold and I couldn't get the adapter locally. I'll probably order the adapter from them and reinstall mine some day.