Thanks for answers. So, I have just received my FAA exemption for instructing with throwover yokes, in Barons etc.
As to the third question: While I hold a CFII and MEI, no one else on field does, and I would like to be able to use a local CFII to maintain MY currency and just for good practice doing competency checks of myself. AOPA says there is a recent change to the FAA position which disallows the practice, but when I requested more info from them about the change it was not forthcoming. Anyone heard more about this?