I do have a copy...just lazy. And thanks again!My 68 is not here but,,, left knob is to left of steering col. at bottom of dash panel-cable goes to left vent. Rt.knob is to right of column(close to ign.sw.) and runs across front of htr box to rt.side vent. Do you have a factory service manual? You really need one,lots easier. I think downloadable at mymopar.com or moparts.com(?)