No, Highway 159. What is this front back business? As far as I know you cannot walk up the "front" to the summit. You would have to climb a route on the wall. Oak Creek Canyon is the walkoff for the routes. Going up the canyon you can expect a good 4 hour hike over a lot of big boulders in the wash. The wash is very pretty with a lot of pinkish striped sandstone.
The front is the wall side accessed from the gated park which I bet is closed. The front is that scenic loop rd. On google maps it looks like there are roads and trails on the opposite side of the mountain. East/west would be better descriptions. Looks like you can make to the wall from the west if oak creek is closed.
I've hiked over the backside to get into Icebox and it was pretty trivial there, but the road jogs far away from where you want to be between icebox and the rainbow wall area. My guess is it would be a burly hike for the payoff. Like others said, don't bother.
I too noticed that road on the map and wondered what access would be like that way. Often, seeing what looks like a road on the map doesn't actually get you a real road. There's one up here I wanted to get on but that just disappears in real life. It would be worth a "rest day" recon for sure, maybe take a Mt Bike as you can often cover a lot of ground that way. I wouldn't get my hopes up too high, cause the locals should have explored that already and it would have leaked out most likely if it was do-able.
But if you wanted to climb it, as others have said above: I'd be tempted to hike in from the Oak Springs parking right off the main highway.