Removing all emissions control/vacuum systems: Good or bad idea?

Still plugging along on Pinkie, my '74 225 Duster.

I live in California and the car was, from what I can tell, a CA market car and it came with the full outfit of emissions control systems that new CA cars had to have in the 70's. Thing is now all these systems aren't needed anymore because the car is older than the cut off date for smog testing, 1975.

If I were to isolate all the old emissions control systems and remove them would I gain power and fuel economy? If I'm wrong and I remove them anyway will the car have a hard time running properly and have problems with pinging and the sort.

If this is a good idea, can you tell me the full extent of things I should remove? I don't want to end up pulling out stuff I actually need.