Hello, I've just installed an AppleX V as well, on a 1.1 PAL board.
I'd like to point out something I've found during my installs and ask something:
1) If you're pretty good at soldering, you won't have problems at removing it, I already did. If you keep the chip pressed on the motherboard while soldering you risk no short circuit through the contacts, and while desoldering you can use a desoldering pump to 'suck' the solder away.
BTW I've been installing modchips on PSX and PS2 for a long time, if you've no practice in such activities it's better you use wires or connectors, or even better you have it done.
2) Question: AppleX V bios is 256KB or 1MB? Can I flash it with any 256KB bios, eg. Xecuter2 4979.06 ?