No headlights, fusible link at bulkhead melted…

Hello,

trying to do some detective work after my headlights stopped working last week. In so doing I discovered the fusible link between the starter relay and bulkhead connector terminal J is melted, the red wire on the inside of the bulkhead looks good, I haven’t looked up under the dash at the ammeter connections just yet.
Prior to noticing the fusible link I had dropped the headlight switch down and gained access to the floor dimmer switch, there is power at the H terminal light green wire on the hd switch and also at the dimmer switch center terminal, but nothing beyond so I thought it might be a faulty dimmer, but when I remove the connector at the dimmer and jumper from the power coming in to either of the other terminals it instantly loses power from the hd switch, if I disconnect and turn the headlight switch off and on again power returns at the switches H terminal… so no load on the circuit it seems to have power, the second I try to jumper either the high or low beams the switch breaks the circuit. I know there’s a few things going on here and they may or may not be related, just looking for assistance in cleaning things up, thanks!

Heath