Emissions is easier to pass than you think. When I first bought the 40 it failed, I took it to the station at Folsom and Arapahoe in Boulder, he tweaked it and I passed. And I passed when my air rail was so rusted out it was non-existent, my carb was actually black inside from backfiring, etc etc. I took it to that particular service station because while calling around looking for a mechanic to help several other mechanics in Boulder recomended him for getting a vehicle through emissions. He has the testing equipment and knows how to tweak, he didn't fix anything he just got me past the test.
If you take it in and fail you can get retested for free in a certain time period if you have a receipt for work performed on the vehicle to fix emissions. If you fail and don't want to spend the money on a mechanic Bruce (60wag) is very good with emissions systems and can probably give you a good idea where to look if you tell him the numbers from the test. You will want the factory emissions manual if you do the work yourself (edit: I have the 1976 emissions manual)
(edit: just saw what year your 40 is in the sig) Once you pass the test register it as a collectors vehicle. No more emissions!
As always, if you need help bring it over.
"Do not go gentle into that good night,
rage, rage, against the dying of the light" - Dylan Thomas