This is using the stock arms, the center section and a 360 degree rotation motor from a Toyota and its switch.
I cut the vacuum motor shaft off and welded a 1/4" bolt to it where the original motor shaft was. Went to Lowes found 1/4" x 3/8" long bushings and some tube. Found an mounting point behind the dash (mine was easy, its an Impala dash, the stock dash may take a little fabrication)
Made a small tab, slotted it for adjustment and welded it to the bottom of the drivers side stock linkage arm