Rc, I have the same 83 as yours and with the Computer you need to set up the base timing, to do it properly you have to disconnect the Comp from the Distributor, you should have a 4 pin connector coming off the distributor, disconnect it and have the truck warm and set the timing at 8 deg on the pointer, adjust the idle speed screw to 550/600 rpms once that is done reconnect the 4 pin connector, the timing will change but leave it alone. you might want to reflash the computer by removing the ground cable from the battery and reconnect it a couple of times.
