That round metal object about 2" from the pos. and neg. posts is a metal gas tank. Sure, it's coated with undercoating, but don't rely on that to prevent a circuit path when the battery happens to shift or pushed into contact during a collision. At a minimum, install plastic covers over the battery connectors to prevent any metal-to-metal contact. A block of wood in that space can also provide add'l short circuit security.

Sherwood

You do realize the post you quoted is 12 years old, right?

Battery hold down thread two pages long?

Yes. Still not recommended despite 12 years have past. People viewing this photo w/o comment might accept this strap is sufficient.

Extrapolate what could happen when the fuel tank shell becomes a potential 200A (or several hundred amps) current path in a direct short circuit - minimally, a fuel-sourced fire.

Sherwood