Jon, just keep running in a straight line until you hit the end, and then start diggin!!

=)

Alternatively, you can go up 4 blocks and start a new set of 3 x 2 tunnels. There's a good chunk of minerals in the entire 5-18 range. Most of our tunnels so far are right at bedrock.. so around 5-8. Probably enough room to go two whole floors higher and still mine it out like this:

The slight offset allows for visibility on the bottom wall blocks.

edit: blogger deletes spaces at the front of lines? Anyway, the dots are there only to move the X's over. Should only be ONE block shifted.

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