I have modded several Canon 450Ds, full spectrum, cooling, even a mono version. It is not too hard to do the mod yourself, i suggest you read Gary Honis' excellent web pages on modding Canons.
http://dslrmodifications.com/
I would be happy to provide advice but my days of modding are probably over. I recommend you purchase a magnifying lamp, the kind with a curcular flouro with a magnifier lense in the middle. They are essential in my opinion for seeing all the small ribbon connections etc inside the camera.