I've hunted it mostly for deer, but seem to always turn up some elk. Like has been said, they turn up in places you wouldn't expect. There are more trees and cover in that country in all the hidden ravines than it looks like at first glance and the elk will hole up in that stuff. Especially with the amount of tags, I think your better off thinking outside of the box and covering country than trying to find places that look like traditional elk country. There isn't a lot of that in those two units and you will definitely have a lot of company in those areas. I have ran into a lot of elk hunters in the earlier seasons when there a far less tags than there is now, so I can only imagine that the unit is going to be pretty packed with the 2500 tags all at once.
I would definitely stay more mobile. Their are A LOT of roads in that country and backpacking just doesn't make a ton of sense cause their isn't enough country to get away from the roads in. The select places that don't have as many roads tend to have a lot of horse hunters, so you won't be alone their either.
You can definitely kill an elk on public land out there, but those elk are being hunted like never before this year, so I would say you're definitely going to work for it. Good luck!