That should be a fairly simple swap. If you are willing to build your own motor, I'd go with a early 22r block and put a 20R head on it. That will bump your compression up a little and you will gain a little in power. (IIRC)
But there are others on here that have way more knowledge about the wonderful world of 22R's. I just tend to let too many braincells get flushed down the toilet too often.