Convertion Pass labs x600 from 110 to 220 V?

Is it possible to convert Pass Labs x.600 or x.350 from 110 to 220-240 Volts?
I think it can be done. I did a 120 to 230V conversion on a X250. It was a fairly easy procedure. Call Pass Labs and ask for direction or send it in.
Easy conversion for a 'qualified ' tech.
My X-250 was converted to 240V.
a couple of wires from the transformer are re-soldered
to different positions on a board - which is marked for
the different voltages.
I think the amp/s would then need re calibrated/biased so you need someone competent with these amps.
Thanks to all of you.
Why don't you ask to the guy at Pass ?