Battery relocation - ground question

I relocated my battery to the trunk several years ago. (1964 Barracuda)
On Friday as I was leaving for a car show, as I was trying to start it to leave the driveway, I heard a click and then nothing. No power to my volt meter, no starting, etc.

After about 3 hours, I tracked it down to the connection between the negative battery cable and the body. The connection was tight, but apparently not a great ground, since tugging on the cable moved it enough to resolve the issue!

The 3/8" bolt goes through the sheet metal floor of the trunk, through the bracket that holds the ford-style solenoid, and then the cable terminal.

I've removed all of it, sanded down all the connection points, and I am ready to re-assemble.

I bought this stuff: https://www.amazon.com/gp/product/B0CRYCXK2Z/?tag=fabo03-20
...a conductive silicone grease. I'm thinking I can put some of that stuff between every metal-to-metal junction to make sure I never lose that ground connection again.

Is there any reason NOT to use such a product to ensure connectivity?