Protecting Body Paint from Weld and Grind Sparks

[Mean 69]

After changing directions "slightly" halfway through a build, I find myself needing to protect a new paint job from some additional work that I will be performing. Specifically, I will be tubbing a car, and also installing a custom roll bar. So, things will get a bit dirty, and also there is a decent chance of weld sparks from my MIG getting onto the body.

I have heard that there are products out there that are desgined specificlaly for this, i.e. won't allow a weld spark to melt through to the paint, but don't know where to find them. Direct experience and advise welcome.

Thanks!
Mark