The metal box has no suicide battery so thats nothing you need to worry about :-)
About Super X.. i dont know if you seen my pic of it? it is detailed enough to spot differences easily.
pic here:
http://arcade.ym2149.com/pcb/ntc/superx_pcb_partside.jpg
Also check your NA-1 and NA-2 boards as they tend to have those leaking caps also.
All of my NA-1 boards are dead or have so sound.
Dead NA-1/NA-2 boards can be fixed by replacing the cap at C5... here is a pic of a fixed C5:
And here are some horror pics of the worst of my NA-1 boards... it...