If you want the best then yes you should have a chassis designed for a 4 stroke. But if you are using and 08 2 cycle chassis i guess you aren’t striving for the best of the best. Many chassis have bolt on seat struts and they work just great. If you have to move the motor off to the right a lot there is a motor mount for that purpose now. In fact if it helps you out i’ll take one of your NEW motor mounts you bought in exchange for one of mine. No charge.