Dont mame it man. Dont change it in any way. If it works good, just clean it up, get it going good and hang on to it. Mame is great, dont get me wrong, but you dont want to destroy a classic, unless it cant be fixed, or whatever.
Where do you live? If its within driving range of Kentucky USA, I will give you your money back for it.
Build a cabinet for mame, or find a cabinet thats already been gutted and use it.
Just my 2 cents worth..