rheostat dash knob .... light dimmer

[steve-0]

the hole in the dash for the light dimmer for the gages is 3/8"

i have found some that require a 7/16" hole.

http://www.colehersee.com/home/grid/cat/119/

[steve-0]

i pulled 3 of these out of the halftracks i have here and all where bad.

i did a search on ebay and found that these are common in big rig trucks.
search "dash dimmer" and add     mack  or peter built or freightliner   ect

i purchased this one.
http://www.ebay.com/itm/300601889782?item=300601889782