I also have:
3 - Braylon Fitzpatrick
3 - Danny Holtsclaw
3G - Jeremy Giles
4 - Michael Fischesser
5 - Toby Alfrey
6 - Dustin Wagganor
7 - Anthony Peterman
7B - Brian Olson
9H - Logan Hupp
9X - Thomas Meseraull -SC
11T - Kevin Thomas Jr. - Jeff Walker
12 - Ted Hines
12T - Jesse Cramer
14 - Lance Grimes
15 - Ethan Barrow
15 - Brandon Whitted
17 - Max McGee
21(?) - Keith Bloom Jr.
21E - Eric Krockenberger
21K - Shawn Krockenberger
22 - Matt Westfall
23 - Brian Karraker
24M - Adam Miller
27A - Andrew Elson
29 - Logan Jarret
29K - Keith Bradley
30 - C. J. Leary
31(?) - Matt Thompson
31 - Chuck Wilson
31C - Tim Creech
35 - Chris Babcock
38P - Seth Parker
44 - Jason Soudrette
51 - Brent Turner
60 - Cory Crabree
63 - Robby Seward
65 - Johnny Mackison
71P - Jerry Coons Jr.
83 - Troy DeCaire
84 - Lance Hayden
99 - Jimmy Stinson

My list is not specifically USAC, but all nonwing. Also, I think there may be a few pavement cars in there. Those listed here have run at least once this year. Not sure but what a couple were typos in a race rundown, like Keith Bloom Jr. in #21.

Good thread. Thanks to everyone. I hope we can get a comprehensive list.