Hmmm... trim the fins on a heater core?
 

I can't tell, from pictures, but it seems that the fins on a heater core are just that -- fins. Am I right in assuming they only increase the surface area to dissipate heat, and don't carry any water within them? I'm referring specifically to the Chevette heater core, which can be had for $17 at Autozone. :)

I started thinking about this because it's just slightly too large for my case; finding a smaller, low-priced heater core hasn't produced any results. I'm wondering if it would be possible to just trim the fins on the heatercore to reduce it's foot print... ? Anyone else have any thoughts on this?

The Chevette Heater Core is $26 at the AutoZones in Kansas City

The fins that you're talking about are only like 1/4" on each side, but you risk cutting up the flow channels. And you'd loose alot of your cooling capacity.

I wouldn't reccomend it. I have a chevette core, so I'm looking at it and saying no :p

why not just cut into the case, and make it fit?

Well, it's sort of a plan A, plan B thing. I originally wanted to lay the heatercore flat along the bottom of the case and put a hole under it (my case has "feet" that get it off the ground). The width of my case is just barely 6", and the motherboard gets in the way on one side. But by mounting it this way, I wouldn't have to remove any hard drive cages.

Plan B is removing the hard drive cage and putting the heatercore in the front of the case. Looks much easier from what you guys are saying. :)

Yeah, then find a way to put the hard drives behind the rad so they get the benefit of airflow over them.

I used a heatercore from a 1987 escort w/ac (i think) and it measures 6 x 7.25 x 2

Just barely fits under the drive cages

Antec sx1000?