Hi Todd, I don't think we've talked about it, but I spent a few years up here working for the Forest Service surveying roads for watershed assessment purposes. I am very familiar with the Heber RD travel plan, and which roads are open to full size vehicles.
The tightest trails in the pics (the ones out of Wallsburg and up near Strawberry Peak) are all open to full size vehicles according to my interagency travel maps. They look like ATV only trails, because the ATVs are the only ones who regularly use them. You can't get an full size pick-up (the local vehicle of choice) down 'em.
Being the guy who used to give out tickets for ATV/off road violations, I like to "know before I go". It sure would be an awkward situation if one of my previous co-workers busted me for being someplace I wasn't supposed to be.
-B.