Their stamping dies wore out over time so the A-body panel fitment and and water leaks continued to get worse. The headlight switch and amp gauge always were subject to water damage in this model design due to their location. Hindsight is 20/20. The did change the amp gauge for the final year of a-body run. To replace this and that is only a fix. It will have the same inherent problem. So a "repair" to OEM has a expiration date. A forever correction requires added shielding. Something to keep the water headed to the floor and away from the electrical. A piece of butter tub attached to the panel to guide the water away from the instrument panel and the fuse box? I mentioned the fuse box because of water damage there in many similar A-body models that have the amp gauge located several inches away ( like my 67 with a rallye panel and different fuse box in the same location ).