While I believe that Long probably has the skillset to excel at RT too, it's a bit of a risky move to move a player away from a position, on which he's played at a pro bowl-level. The expression "if it ain't broke, don't fix it" comes to mind. I know that RT is "broken" at the moment, as Jordan Mills just isn't a starting caliber player. But we could potentially be changing a pro bowl-guard into an average RT. Not a very good trade in my opinion.
But heck, if the coaching staff believes that Long could be good at RT as well, and thereby upgrading the line by making that move, I'd have to trust them.