[Test-Equipment] Calibration for Radio Shack DVM

[Bill Abate]

Just got a used RS 22-174B to replaced my old one.  Really 
like the unit despite being Radio Shack.  The ranges check 
out fairly close to my standards except resistance.  Seems 
like there is a 4 ohm error.  Not really significant but I 
opened it up any way.  There are two pots inside, R70 and 
R71.  I don't want to screw it up.  Anybody have schematic 
or alignment procedure?

Thanks,

Bill, K3PGB