Russ,
If just the high beams don't work, check for power at fuses #1 & 2. If that checks ok, then it's either the headlight bulbs or the wiring / connectors between the fuse panel and the headlights. Left and right high beams are fused separately. Low beams are also fused separately...total of four fuses (#1,2,5,6) for the headlights.
If you have no lights, check the headlight switch.
You can also make voltage checks at the molex type connector for the hi/lo beam switch.
John
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