Forget what I said, but the board has nothing to do with it. Note in the reverse photo that you can see reeding on the '86 but not on the '78. This suggests that the camera was directly over the '78, so the '86 would seem slightly smaller. However, in the obverse photo, you can't see reeding on either coin, and the '86 is just a tad larger. This suggest that the camera was positioned farther to the right but still closer to the '78. Chris
For their value in silver, you can probably find nicer coins. Even nicer other Morgans. The local gold & silver place has bins of "cull" Morgans for $20 apiece that are in better shape than these.