Hello Michael;
I am sorry to inform you that Jim Thomerson is no longer with us. Jim was an outstanding modeler and a great guy. He was a member of the club here in St. Louis, MO, the Lafayette Esquadrille, for many years and at the time of this thread publishing, may have been retired and relocated back to his home town of Austin, Texas. I can't remember what year Jim passed away, but he is missed and thought of and mentioned frequently. This thread brought to mind his Cheap Thrill 1/2A stunter that was published in Model Aviation and I think I have the plans for it. I need to look into that again.
Good luck with your engine project and I'm sure Jim is watching and interested!
Type at you later,
Dan McEntee