Konami Aliens EU/Japan conversion question

[GalileoFigaro]

Hello.

I have a japan Aliens PCB. I want to know, if is possible make a conversion, and install eproms with the EU versions (with the APC scenes) but keep the Japanese sound eprom.
Are there hardware differences between the Japanese version and the European/USA version of this board? Other than that weird USA version with two pcbs

Than You

 

[nem]

I think that's possible. I remember @system11 doing this (although it might have been in reverse).

You could always try it out in Mame first.