Steve,
So I put the reverb tank back in the amp, hooked it up and everything seems to be working fine. I don't know what the tech guy fixed or replaced, but it was something on the board where the intensity pot is, there is some heat burns on the board just under the pot where he did some soldering. But I will find out.
The reverb works, don't know if it as strong as it supposed to be. I have a new tank coming from Tubes&more, is has the long delay, which according to info on this site is the proper tank for that K150-8.
I will install that one when it arrives to see if the reverb is any different.
But so far so good.