This sweep and the Snake Bowl (early) sweep can be done by one person (if you do huge zig-zags).
Wait until 1530.
Close the Sawbuck gate at Snake Top.
Zigzag through Sawbuck between Snake Bowl and Doyle's Dive ending at the T-Road No-Jumping Bump (don't get too low).
When the Snake Bowl (early) sweeper joins you, call, "Crest Top, this is <your name>. Sawbuck and Snake Bowl are closed and swept."