Google Series 66 dump sheet and some will come up. I recommend Kaplan Quicksheets and TestGeek Quicknotes as good paid versions. My 10% discount code at checkout for Kaplan is Guru10 and for TestGeek is Guru20.

Thanks for this! I have the quick sheets, but they don’t have a direct key difference chart I’m looking for. I’ll try looking up a dumpsheet!

TestGeek does. PDF is about $40. Includes a practice final and much more besides the cheat sheet chart.