Hi grumpy, from what I gather from Rosco's first post is that the original Briggs had a terminal failure. Chances are that the hydro transmission may be fine, for now at least. If a engine transplant is not a too involved project, wouldn't it be justified to give it a go? It might turn out to be a successful exercise.
Please do not PM me asking for support. Please post your questions in the appropriate forums, as the replies it may receive may help all members, not just the individual member. Kindest Regards, Darryl