Gene, now that we know what your doing, if the numbers are all the same for all parts as well as size (10pt) maybe a pad printer would be a more fitting solution. There are may inks available that may fit the needs.
You might want to check with NASCAR to make sure that what you do fits their requirements. I'd have your clients sign a disclamer to. NASCAR is tough on rules and you don't want to be party to a lawsuit if they suspend a team for infractions.
Just a thought.
Marty
Martin Boekers
1 - Epilog Radius 25watt laser 1998
1 - Epilog Legend EXT36 75watt laser 2005
1 - Epilog Legend EXT36 75watt laser 2007
1 - Epilog Fusion M2 32 120watt laser with camera 2015
2 - Geo Knight K20S 16x20 Heat Press
Geo Knight K Mug Press,
Ricoh GX-7000 Dye Sub Printer
Zerox Phaser 6360 Laser Printer
numerous other tools and implements
of distruction/distraction!