I have a 48" Wright Stander large frame and it currently has a Kawasaki FH541V KAI engine on it. It is a 17hp and I am looking to upgrade it. How do I know which engine upgrades are appropriate. I know that I have to match up the shaft size. I would like to upgrade to at least a 19hp or possibly 21 or 23. I would probably get the heavy duty air filter as well. What are my options here?