Of course Britcom meant evaporator under the dash. I have used both Vintage and Old Air Products on a 41 to 46 with equal results. I have noticed that they will cool very well at 55-60mph but at 70mph not so good. Since there is no weather stripping, just windlace, I think the air rushing past the doors and other not so tight seams pulls out the cool faster than the a/c unit can replace it.
