using an SS White x-ray transformer

Hello everyone, first time to post here.  Here's my situation:  I have a 90 Kv,
7 mA transformer from an older 1978 SS White x-ray generator and I want to
readapt it for Tesla coil or other use.  With testing using a variac and meter,
I've found all the windings to be functioning properly.  Here's my problem: The
transformer was operated in transformer oil originally (which had been drained
out) and I've been told it is very difficult to remove all of the air and
moisture from the tyranny upon refilling without a vacuum pump and jar.  Since
I don't care to invest in the expensive equipment required for the job, I'm
wondering if I can operate this transformer at one half of its output (50Kv, 3
mA) either dry or just filling with mineral/ transformer oil (or even kerosene)
without vacuuming?  It was difficult to obtain this transformer and I'd hate to
burn it out, but I'm dying to experiment and I'm hesitant.  I already know it's
not current limited and that's one reason for the variac use.  Any pointers
would be appreciated.
By the way, this transformer is set up kind of like a neon transformer:  one
leg has a maximum of positive 45 Kv-- the other leg negative 45 Kv.  
John Bowers