I personally like using a headlamp since the light goes to where I'm looking. But if you're interested in a clamp on, battery powered LED type, I found this one at Amazon -Fulcrum 20019-301 Battery-Operated LED Clip-On Task Light. One reviewer said the clamp opens to a maximum width of 3.5" which would work with the Performer.
I have a cheap clamp on portable work light that I use when i have to cook in the garage , but out on the patio , the headlamp is the way to go....as pete said , the light is always pointing where you're looking...and they are cheap nowadays
I have a Maverick GL 400 that I picked up recently at Amazon. I like it because it has a hinge on it so it will lay flat on my performer when the cover is on. No need to unmount it from the table.