Well, cutting the hole was quite a bit of work – I tried several methods, but the best ended up being a combination of a jigsaw with a metal cutting blade to rough the hole out and by hand to clean it up. I still have a pretty ‘ragged’ hole, but that’s not a big deal.
Before the mod the temperature would sit around 30C while running, and climb to a maximum of 48C after I turned it off.
The new fan is very, very quiet. I can clearly hear the other two fans working away (they have to be changed next, but I wanted to stick to one change at a time). The projector seems to be running a little ‘hot’ however, as the internal temperature climbed to 33.5C after running for 90 minutes. It seemed to be still slowly climbing as well. This fan may not have enough ‘static pressure’ to push air out the vent holes — or my opening may not be big enough.
I’m going to enlarge the opening and see how the fan does. I may also try opening up the vent holes a little to increase air flow ‘out’.