Changing coolers on iMac 20"- can it be done?

Ok, what i want to do is buy some coolers more efficient (runs faster, more CFM, etc) than the ones that came inside my iMac so I can get them to an Apple Store and ask them to change it for me (I'm not that good to change it myself ).
Anyway, here are a few pics that I got on a Google search so you can get the idea:






This last one is upside down.

I want to replace those 3 coolers that can be seem on the first picture, but the most important one would the CPU cooler for sure (seem on the left in the first 2 pics).
So, are there any coolers that would fit there for what I want to do?
I was thinking that maybe I could buy spare parts for the 24" model, but I don't know if it would fit or if it would be any different than the 20"model: iMac 24" for parts. speakers, camera, plastics, cables - eBay (item 380205760452 end time Feb-17-10 13:15:47 PST)
Any ideas?

There are softwares that will help make your fan spin faster, actually. SMC Fan Control would be an application that comes to mind.

I do have SMC Fan Control and use it halfway it's capacities which helped a bit but my concern is the fan's lifetime using it on full.
And remember, I live in Brasil so it's VERY hot here...
Someone suggested on OC forums that I should change the thermal paste which I think is a good idea too.

caincha said:

And remember, I live in Brasil so it's VERY hot here...

Click to expand...

We can't remember what you have never told us!

Add your location (Brazil) as part of your profile...if you wish everyone to know.

- Nick

Ooops, I forgot that...
Thanks for the advice, will do just that.

Anyway, I change my mind about replacing the original coolers 'cause I guess the issue is that my room temperature is way to high.
Actually, is about only 10 degrees below the temps shown on my iMac so I'll change the thermal paste and ask the guys at Apple Store to also clean my fans, which should help.

Thank you guys for the help and apologize for my bad english.
Cheers!

caincha:

Something to remember about electronic equipment.... It's not necessarily the high temperatures in Brazil that are detrimental to your iMac, it's the high humidity that does the damage.

I've lived in the desert areas of California for a number of years where the daytime temps reach 100 degrees F and higher every day but with very low humidity. Not much wear and tear on electronic equipment there.

I also lived and worked in Honolulu, Hawaii for a number of years. Average temps around 85 to 88 degrees F but with very high humidity. Lots of wear and tear on electronic equipment that wasn't in an air conditioned area.

Regards.

I do know what you mean, I lived near the ocean on south region here in Brasil and even though the temps weren't too high (except on the summer) I had a lot of problems due to corrosion and humidity.

Back to my plan: I was thinking on buying Arctic Silver 5 but didn't feel too safe about it's conductivity on such a small space so i chose MX-3. Let's see what happens once it's applied.