here is the inside of the IDM..you pull out the 6042 resistor thats in this pic and solder in a new resitor..the resistor you put in depends on witch IDM you have,,the 110 or 120...
To convert IDM 120 to 140 you need a 73.2k ohm resistor. .5w 1%.
Digi-Key - PPC73.2KXCT-ND (Manufacturer -...