@Damion
A firmware update might be usefull, I never messed with that on mine, don't even remember if it has the lastest firmware (almost did but was afraid to ruin a good working card).
It's been running like that for months but to be honest I don't fire up my 4000T that much except for some dev stuff once in a while. When I do it's normally up for 2 to 3 hours but it's not on 100% CPU load.
Good 50ns ram is essential, maybe there's even better.
Also, don't forget that there were MK2's running 040's at 40Mhz, which means they used an 80Mhz clock (040 CPU uses half clock rate), so 80Mhz won't damage the card, just be sure to use an oscillator socket to be able to exchange them easily and keep an eye on CPU temperature.
I really got to try 90Mhz or more
