ARC VT100MKII retube and bias input tube

DOES ANYONE KNOW HOW TO BIAS THE INPUT TUBESIN A VT100MKII,or is this something that needs to be done at the factory.the output tube bias is a no brainer ,but not so for the inputs.thanks for your input.
Contact Chris at Audio Research, he has provided me with the procedure. You will also need the schematics and parts list. You will need a DVM and small pot. adjustment tool (tweeker). I have the procedure, but it is copyrighted...
Go to radio shack & buy an autoranging multimeter & a set of probes (or adapters ) that will grip the contact point & then follow the above advice.