2180cc should be a 78.8 crank and 94mm barrels, very similar to my 2165. The 15cc difference is the crank stroke, mine is a 78mm.
Go for it, but I would want to know the specs like Al Blanchette. R & R engine in a Speedster shouldn't take more than a day, especially if you've got two guys and a good set of tools. Much easier than a Spyder IMHO. And I've done both, many times.