Hrrrrm.. It seems that pentium 3 rated Tjunction is around 80C, recommended 70C operational.
Currently Xbox reports 55C CPU. If Tp4 cranks the fan to max, it runs 46C. 55C should be more than adequate, since this era of cpu didn't throttle down, this is as high as it goes.
Would consider further mods if for whatever reason, Pro-Halo-1 became a thing again.
Maybe cut out the metal grill part in the back. Buh.... kind of a hassle for not much gain.
Tp4 could switch to an SSD, buhh, you kinda don't get that feeeels unless you hear that mechanical go Brrrrr.. Then again, that's 5 watt of heat right there. Quite alot of load shed.