For me the PS2 games are not so tricky because I have Magic Boot 3.6 and a set of Magic Keys 2. The only reason I wanted to know what you'd done is because the key which holds the rear switch down when the lid is open keeps coming unstuck. I can usually get it working by stuffing a strip cut from a ready made meal microwave dish between the strut and case so that it pushes the microswitch down and keeps it there.
I have downloaded a YouTube video showing the method of disassembling the PS2 slim case, but I just wondered if it was actually feasible to bypass that particular switch by hardwiring it. The other two keys stay in place alright, so it's just that switch I'll have to bypass.