do your heat exchangers work, put a pair of second hand exchangers on my 57 oval, it has a later 1200cc engine, surprise , surprise they work really well, and i mean really well, the passenger side was not blowing as hot, so i reved up the engine and was showered with broken peanut shells, some kid must have been stuffing the nut shells down the vent, after about nine blasts of nuts that side is blowwing as hot as the drivers, surprised as they are pattern exchangers, they work better than the insulated factory ones i had on my notchback and better than any beetle ones i have ever had befor, toasty.