A couple of years ago I released a version of RetroPie for RaspberryJAMMA. It's still online somewhere I think but wouldn't support the current Pis (can't remember if Pi3 was out yet it may only support Pi2 and earlier). I can try to find the links if you're interested let me know.
If you're keen not to use ARpiCADE as the software I'd recommend Recalbox, there's a version for RaspberryJAMMA done by a member here called Ouaibe (see here:
viewtopic.php?f=12&t=541 ).
Especially for a vertical monitor I'd recommend just using ARpiCADE really. It's the only one aimed at cabs. Then again I make it so your millage may vary...
What feature of RetroPie are you after? Both RetroPie and ARpiCADE are based on Raspbian so a lot of stuff is compatible between them both (generally but not always).
Attempting to use the RetroPie install script on top of ARpiCADE would not be recommended though, it would almost certainly just result in a borked SD card. If it didn't completely break the build you'd end up with 2 separate installs of Retroarch (and the cores) with none of the RetroPie bits actually integrated into the system.