I'm planning out my next system have decided on the Antec P-180 case.
But I would also like to use a Vapo LS for cooling. But then I run into the problem of the PSU sitting in it's own compartment at the bottom of the Antec case.

Any suggestions how to put the Vapo and route the evap head to the CPU?

Stand them side by side and cut a slot in the case side panel. If that's a non starter then get a Lian-li PC60 and mod as usual.