HELP - Need Tube Amp Technician in North Dallas

I have two tube amps that need need some attention.

I haven't had any luck finding a local tech (Lafayette, LA), but I will be traveling to North Dallas this weekend to visit my son and thought I might have better luck there.

One amp simply needs 8 capacitors replaced.  The second will require more skill.  The auto-bias circuit stopped working.  I was told by the former distributor that this circuit is a single resistor that controls a group of resistors.

Any and all suggestions are welcome.

Thanks in advance.