I know I shouldn't recommend this to someone that obviously doesn't know what they're doing, but if you really want to do it, you need to identify the exact makeup of the potting compounds, there are oftentimes chemicals which can be used to dissolve the potting compound but leave the circuit intact. Such an undertaking is not a good idea for someone that doesn't know what they're doing. It'd take a lot of research, and likely the chemical involved you wouldn't be able to get a hold of. There are chemicals which can be used to actually remove the plastic package of IC's and expose the internal die. Some companies use it to reverse engineer competitors chips. Not to mention you can find free schematics for ballast circuits on the net without having to take apart yours.