Aux batteries

Have a 2008 vcv3,looking to add 2 golf batteries to engine compartment,has anyone done this or similar ? Tried sportsmobile but don't install under hood work,don't want it in the house portion and under van is probably a pain,anyhow any suggestions,will pick up a 220 watt soler panel in Miami in the next couple of days,thanks for any ideas.

4 wheels in this thread has done it. https://sprinter-source.com/forums/showthread.php?t=31125 In the quick links drop down in the blue bar above pick "Today's Posts" and it shows up as well. This lists all the current threads and the one I referenced was started this month.