I thought it was a great article from a guy with a "can-do" attitude.
Feasible? Oh heck no, but a fun build, if you like making things and/or solving problems.
To each his own I guess and its not like its a rare tractor
While my opinion is the K series Kohler is the best small engine ever made for a garden tractor. The Predator engines are, for the most part as good, if not better than some of the crap engines the big names such as Kohler and Briggs are making now-a-days.
He'll likely have to stretch the wheelbase to fit a 60 inch deck under that tractor but based on his problem solving skills shown in this article, he will no doubt be able to conquer that.
I see he hasn't been back to the site since 3 days after he joined but maybe we'll get lucky and he'll come back to give us an update.