knob depends on the heater -
factory standard ones [see page 2 - recirculating unit that Bruce refers to] installed at the factory did have a knob that matched the others - the cheapest, dealer installed, which are like the later AD [or maybe ND] heaters had a different knob on a slightly different switch - but all mounted in the little panel left of the glove box that 'mirrors' the ashtray
deluxe heater [page 2] had a whole assembly there that has a 3 speed fan switch
Bill
