if you are still under 70-80% with the extra modules it is possible to add an additional busboard
it is also possible to make double (or triple) headed power cables* - I think intellijel make these or small flying busboards that might be suitable
it really depends on the space in the rack the 2hp modules can also be quite deep so this may have an impact on which solluttion will work best for you
*this is really quite easy and inexpensive to do and can be done with no specialist tools
Utility modules are the inexpensive, dull polish that makes the expensive, shiny modules actually shine!!!