This reminds me of the Poor Man's cruise control I did for our 71 camper-
cut a piece of wood into an arch that followed the gas pedal edge as it
arced thru its travel.  Notched the wood so it would catch a metal lip I
bolted to far edge of gas pedal.  Made a pivot point in bottom of wood
piece and a bracket bolted to floor behind gas pedal so when pulled foward,
pedal would be held by a slot.  Attach a choke cable control to dash and
mount other end thru floor and back up between gas pedal mount and bracket
for slotted wood.  the cable attaches to wood pivot so when knob is pulled,
pedal is held at position of slot!  Pushing knob released it, AND I
installed a rod on brake pedal bent so it pushed a rod coming out of side
of slotted pivot when you panic braked and kills gas pedal control-  Worked
great for those long flat hauls to Fla. when you (a) want to rest foot by
laying up on dash (b) switch drivers while tooling down the road (c) take
off your shoes!  Of course this works not as well on mountains, but then
was a very cheap system!!!!  MB in NJ  (I miss that 71 camper!)