The Bils are monotube shocks, and compress more compactly, while extending well, so that the shock travel can occur within a more compact package.

The Ranchos don't get short enough to work as well with a PML, because if you fully stuff them, the piston rams the body.

The same goes for the 3" SL btw...which is why they recommend bumpstop extensions...to keep from over compressing the shocks due to the lost uptravel.

The Bils work with out any lift at all, all the way up to the 3" SL range....they even worked pretty well with the Revolver Shackles on opposite droop.