Mesh Analysis with a ideal current source
I have no idea what setup I should use for the two meshes with the
  ideal current source.


Here's a hint:  the current source provides the following equation:

\$ 1A = I_C - I_B \$

This is analogous to having a floating voltage source when doing node voltage analysis.  There, you must form a supernode enclosing the voltage source and add the equation relating the voltage between the two nodes enclosed to complete the solution.

Here, you must form a supermesh and add the equation I've given above.