The track deal is good but they will not swim.
Check your serial number on the Max page, later iv came with 27 or 29 Kawasaki efi engines which are getting hard to find, 23hp or better briggs or kohler are a good choice. Some diesels have been installed but rpms and clutching have been isuues, weight is alot that high in the air. Duals are worth a try and a report back would be informative for others.

Personally I would try to put it back stock and shake it down from there for ease and a good base point.