I think you keep the starting 5 were they are.
Newhouse, Lang, D-Smith, Sitton and Bulaga.
OT Sherrod and Datko should be worked at both OTs.
OG/OT Barclay should be worked at RG and RT. (and hopefully could fill in at LG if needed)
Van Roten and Gerhart (yes brother of Vikings RB Gerhart) should focus on Center and maybe some OG but mainly Center.
If Joe Gibbs can play Center focus on that, if he can't focus in on the OG spots (and maybe RT if he can do that)... (as far as I know, not related to the famous Joe Gibbs)