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If you read my entry "Puzzling Electrical Problem" you will get up to speed.
What I need assistant, advice with is how do I jump the headlights to see if my high beams work.
I have tested the entire cab for continuity ( everything tested good) I have replaced the dimmer switch and the headlight switch 2 times( going for a third time since it does not light up the courtesy light).The blue and light green wire in the dimmer connection test with power.
What can I test next?

Well ,at the dimmer switch are the two wires that run the headlights both the reg. lights and the high beams the other wire is the HOT from the headlight switch ,so if You want to see if the high beams work take a wire from the positive of the batt. thats long enough to reach the dimmer switch ,I would use an in line fuse on the "jumper" wire and take the wires free of the dimmer switch and touch one of the wires at a time one should lite up the reg. head lites ,one should lite up the high beams and one will do nothing,that would be the HOT coming from the switch.If the high beams do not come on it could be a bad wire from the frist head,drivers side, lite to the dimmer switch or maybe it could be both of You're high beams are burned out also check the terminal block mounted to the fender,drivers side, for a rusted screw connection or a bad wire connector.
Also if that does not lite up the high beams you can take that same "JUMPER" and touch the wires on the the terminal block one at a time that should lite up your low beams and your high beams and the parking lites,just don't touch the black wire thats a ground.
Pete

I have new headlight harness and new front harness so the wire are good there also I have new tailght harness and frame harness so wires are good there.
Could the horn relay be a paroblem. I also have I new one. I could have wire it wrong. The manuel is for a generator and I have an alternator.

I can't imagine a circuit much simpler than the headlights. Check for voltage from the headlight switch to the dimmer, then check dimmer output to the high and low beam wires. If you've got voltage to the light sockets, replace the bulbs. I assume the harness wires are color-coded? A simple multimeter, or even a test light should be all that's required to check those circuits, assuming you can read color codes. The voltage from the switch will go to one terminal on the dimmer, and switch on and off as you operate the light switch. From there, there's only two wires, one for hi beam, one for low, so the circuit has to split somewhere to go to each headlight. Just follow the wires, checking for voltage anytime there's a connector or junction block.
Jerry

Edit: Be sure the headlight bulbs are grounded, or nothing will work.
Jerry

I wonder if you have the connections wrong at the headlight plugs. The center term is not the ground.

No that area is right on. This headlight problem happened when I replaced the taillight haress and also the frame to taillight haress. When I started this project I discovered that the PO had jimmied all these wires, so I removed them all and installed correct parts. I when as far as replacing the headlight harness and front firewall harness new headlight switch new dimmer switch. I am on the second headlight switch as both had issues. I belive I will be going on my third headlight switch as it does not light my interior light when I turn the knob, the other ones did. It funny when you replaced a part and feel totally sure it is not that part. You say "It's NEW it can ot be the problem" well that was one of the problems. I will be working on the truck this weekend. I will post my findind.

Update:
Today I had some time so I started testing my wires again. This time(with the help of the forum) I started at the headlights and worked my way to the firewall. I have no voltage at the green wire(highbeam)therefor I worked my way to the firewall connection and there I found the problem, the connector was bad. The thing that drove me crazy was that the entire cab wiring tested good. I tested the outside of the wire plug at the firewall with the inside of the connector and it failed the test. I drove to Napa bought my parts and finally highbeams. Now, I have to look my interior lamp. It does not turn on with the new switch.
Thank you all for the input.