removing factory paint from plastic shells

When you custom paint an engine or car, do most of you strip the existing paint or do you just paint over what is there? If you just paint over the existing, do you worry about losing details? If you strip the paint, what do you use as not to eat the plastic shell and the details?

Next. When you are applying scare stripes or other striping, how do you mask it off?

Thanks,
Jellen3

I actually sand down the old lettering, then spray with primer, then the color of choice, and use decals for all numbering, striping and lettering. If you are going to add details, or kit bash, do that before you use the primer.

Remove the paint or sand the lettering as stated above. The old lettering will show due to the difference in the thickness. This will show under certain lighting conditions. If you sand make sure you feather the area around the removed lettering.

See: http://www.hosam.com/