Martin and Collins can be good tackles at RT if needed. Frankly I rather them swing out than Chaz Green.
At this point, I agree. If Green shows he can handle it and be the future at right tackle, then I'd rather not disturb the rest of the line and just insert him. However, I want the best protection on the field even if that means Martin goes to right tackle and Leary comes in at right guard if Free gets hurt or Collins goes to left tackle and Leary to left guard if Smith gets hurt.
Leary has shown that he's a starting guard (and frankly, I can't explain why some team wasn't willing to give up a pick for him other than his degenerative knee condition), so we need to take advantage of having six capable starters if we're put in a situation where we need to do that.
One thing I'm curious about is Leary's ability to play tackle. He started out at Memphis as a backup tackle, then made 36 consecutive starts at left tackle before moving to left guard during his senior year because of injuries. Since Dallas knows he's a backup this year, I wonder if the team will give him practice time at the tackle spots to help justify dressing him for games. If Dallas takes seven linemen to games, then Leary could play guard and tackle and Looney could play center and guard.