The hieight and width of the heater cores are the same.     The length
is different along with the connections.  Why in the world would you
want to risk putting those leaky rear cores in the front?

Dan Barrett wrote:

>All:
>  This raises a question which I've been pondering since last winter, when
>the rear heater alone saved my bacon -- in a blinding snowstorm, my
>radiator clogged and the temp gauge spiked.  I cranked the rear heater
>(my front heater blower is dead), the engine temp went down to
>acceptable levels, and I made it to my destination not long thereafter.
>
>  This year, I'm thinking about finally doing the dreaded front heater
>blower / heater core dashboard massacre, but given the output of the
>rear heater core and the cost of a new front heater core, has anyone
>ever tried putting a rear core into the front heater box?  I realize it
>would take some modification to get the rear heater core mounted in
>there, but do I recall correctly that the black plastic portion on the
>core which mates to the heater control valve is the same on both cores?
>
>  Apologies if this has been asked and answered before.
>
>Best,
>d.
>1990 GL -- "Mudskipper"
>
>
>