DD- there are two coolant type heaters that I know of for the Cobra -- not sure how exactly they would fit in the FIA ERA dash space. --
The one that finish line sells is basically a square box 7" x 7" or so. I have one of these on the shelf , was going to use it ---but to try to install it into an *assembled* car is a royal PITA-B'.
http://www.finishlineaccessories.com...roducts_id=108
But then I found the solution ; "Vintage-Air" Heater/Defroster kit model 50610.
This retails at $229.95 ( you might be able to find it cheaper online somewhere.)
-- I found one on ebay from a random seller -- without too much difficulty. (item: 390131433409)
It is a similar unit that the later HST CSX 4000 units use.
http://www.vintageair.com/catalog09/...talog%2023.pdf
Here is the old instruction sheet -- they dont have the new version online yet.
http://www.vintageair.com/DownloadsS...%28Inet%29.pdf
This is a slightly more modern version of the VA unit that I used in my superformance (replacing the stock unit that I detonated with water pressure.) We grafted on the door control unit from the SPF unit to make the heater door work electrically - they now do this in the new kit.
the controls can be de-mounted from the dash pod they send you and used anywhere you want.
They give you just about everything you need with the exception of the top of the defroster ducts -- I am sure you can find-make those.
What they dont show very well is the bottom heater/door flap that opens downward. --If you look at the size of the unit - it should tuck up neatly behind your firewall.
I put mine on a 3/32" plywood backboard (painted black) and then attached that to the firewall.
here is mine during install.
The defroster tubes come out of the 2 holes you see on the "front" of the unit, the "heat" is dispensed from the bottom. The heater core inside the unit looks very tough and it not the traditional "radiator like" assembly but more like a transmission cooler tube matrix, if that makes sense.
the only problem we had was the odd fittings that are attached to the heater matrix, I had to work on it a bit at first to make it seal, but it has been trouble free since September (over 1K miles) -
best part- the wife now gladly rides in the car in colder weather, and asks me to turn down the heat sometimes
Best Regards, -
Steve