Here's what I did to my '79 20R:
Removed all the EGR stuff, and made blockoff plates out of some 1/4" steel.
Removed all vacuum lines, and replumbed it all using the Haynes manual (get it from AutoZone), and used the Canada emissions diagram (very few lines).
Took off my air pump, and all supporting junk that was on the passenger side inner fender.
I did leave my charcoal canister, since it's tied to the gastank.
I also rebuilt my carb at the same time. Now it seems to run better, but now it's down again as I'm swapping the motor over another frame/body.
Good luck
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