Hi Minus,
You could have completed an IGI written test (to all intents and purposes the same as the CFII), visited your local friendly FSDO and had an IGI certificate issued, that would have solved the teaching of the ground school problems (You would have been exempt from another FOI test).
Somone asked what the point in having an FAA CPL. Well you have to have an FAA CPL/IR before you can gain an FAA CFI / CFII or MEI instructor rating. Guess what I'm doing next year when I've finished my JAA ATPL written exams.
Best wishes,
Charlie Zulu.