Hood Turn Indicators 'ground' issues

I'm putting my hood mounted turn indicators on my '69 Cuda and notice that they no longer get their ground connection through the sheet metal like they did before I restored the car. These indicators just have a single signal wire that runs through the hood channels back to the firewall near the master cylinder, where they connect to the wire harness. Apparently there was originally enough of a ground connection through the original hood/hood hinges, etc. I was meticulous in the restoration, and I'm not really surprised that I lost this ground connection, because I've got a lot of paint on those parts that were probably barely covered when new.

I'm not sure if I'm going to run a separate ground wire from these indicators to the firewall. I really don't want an extra ground wire service loop there to deal with.

Has anyone experienced this before? Appreciate all the help!