Please give me advice about an ARC VT 200 amp


In a few days I'll be the owner of an ARC VT 200.  I've never owned a tube amp, much less one of this size.  I'm reluctant to plug in this amp for fear that there may be some considerations that I'm overlooking.  I haven't found much info about the operation but I did read that a variac should be used to bring the voltage up, and that a shorting pin needs to be installed in the balanced inputs if the single ended inputs are used.  I've never heard of either a variac or shorting pin, and I'm wondering if you could please give me your thoughts about these items, as well as anything else that I should take into consideration before plugging it in, and during use.  

I will be using the single ended inputs.  The amp has not been turned on for 3 years.  I was told that the owner was fastidious about the maintenance of the electronics and the tubes.  Any thoughts would be greatly appreciated. 

Thanks
irish_tim
I am surprised about the hesitation to power it up after being stored for only 3 years. That doesn't seem very long at all. We took my father's D-79 that wasn't powered-up for about 15 years and plugged it directly into the wall (didn't have a big enough variac available) and no problem. Maybe just got lucky but ARC tends to use high quality components especially back in those days. It seems 3 years is nothing.
I agree with j_stereo, that 3 years does not seem long enough to pose a problem for the caps. The 6922 tube bias thing is however, extremely real and they are a bit of a pain in the a$$ to bias, requiring 2 digital multi meters, some expertise and patience. Best left to someone with experience. Improper driver tube bias can/will take out output tube(s), final resistors and possible cause mini-fire.
@noromance , The technique I offered works just as well and is a lot cheaper. Based on your post I suspect you didn’t read my post all the way through.
@atmasphere I did read it all the way through. And with increasing incredulity with each sentence! However, I'll defer to your experience. I always play by the book when working on tube amps.
I always power up an old or used gear the first time using a DBT (Dim bulb tester) as atmasphere suggested:

http://www.geek-tips.com/2015/11/22/dim-bulb-tester/

Better safe than sorry!