Swamp (?) A/C cooling idea - would it work and for how long? Options

[perrysan]

Years ago at a swap meet I picked up the under-dash AC unit for my 914, and the stubby center console to go along with it. I ended up putting it in storage because I but didn't want to sacrifice the horsepower to the A/C compressor,. For me most drives are spirited but generally 30 minutes to an hour.

This got me thinking about an alternative approach that would involve placing a medium sized chest cooler in the frunk (large enough to hold a couple bags of ice or chill pack equivalents) and plumbing the lines from the under dash unit to the frunk into cooler, adding a boat sump pump tied to the A/C blower fan, and using a chilled water approach to getting coolant to the under dash unit.

My question to the group is has anyone tried this and would ~40 quarts of icy water provide much cooling for very long?

I know I should just bite the bullet and get the classic auto air upgraded compressor...