It should be fine to run without reverb and without a fan. Just be sure to keep it ventilated if not using a fan. The reverb tank is a non-issue. When I got mine it didn't even have a reverb tank. It was fine but it just didn't have reverb.
Russ even with the fan removed is this a good idea as its a bit cramped in there for any airflow around the power and preamp valves etc with my MKIV short head .
I always thought the fan would help keep the trannys cool too as they can generate heaps of heat and so give a longer working lifespan...
Thanks for the reverb info thats much appreciated everyone ,
Now disconnected !!..
Without a fan you just have to use an alternate method of keeping the amp cool if you are getting it hot. A separate fan or if rackmounted a rack fan would do it.
When I switched out my C90 to a EVL, I found out my reverb tank wouldn't fit, so I took it out. Never use the reverb anyway. Much prefer the reverb of the G-Major. Just make sure you your reverb knob is set to "0" and you will be allright.