How do you mount electric fans to a radiator?

[cgrey8]

As I mentioned in another thread, the cooling efficiency of my fans could be improved. While looking around at my options, I could come up with some kind of dam that would keep the air from blowing straight down instead of through the AC condenser and radiator. But there'd still be a lot of little holes here and there that air would be able to blow through. Even if that keeps the temp down in the summer, what about with the AC running? Will I be right back where I am now? Pushing air is much more difficult than pulling air.

That being said, I got to looking at the area behind the radiator. With the engine mounted so far back in the engine bay, I think there is enough room to mount those fans between the radiator and the engine. If not, I think a flex fan would fit. It'd be tight, but I think either option is doable.

I've seen electric fans mounted directly to radiators before, but how? What fastener is used that will secure the fan, but won't hurt the radiator? My concern is that if whatever they are requires that I do something to the front of the radiator, that means pulling the radiator to get the AC condenser out of the way. I'd like to avoid that if possible, but I'll do whatever is best and at this point, mounting the fans behind the radiator OR installing a flex fan just seems to be the cleanest and most efficient way of solving the cooling problem now and when the added heatload of the AC is online.

Thoughts?