has anyone added cruise control to a 87 and older non cruise control truck? the 87 i built had it all stock. but my 86 doesnt. other then the vacuum assembly under the hood for the carb what else is there? ive been looking for a diagram for wiring. from what ive found it looks like its just the vacuum assembly with a plug in the back for the switch. but im not sure what year the assembly im looking at is. id like to add it without changing a column. possibly run it through a toggle or a push button.