I have for just at few monts ago saved my A4000 for an leaky battery, the guide I used was:
http://amiga.serveftp.net/Battery.html http://amiga.serveftp.net/RTCrepair.htmlIt can be a bit tricky business to repair the tracks on the motherboard, but it's doable. However it sounds like you must have a major leak when you A4000 refuses to boot. The best thing you can do in your situation is to take the moterboard out of the kabinet so you will be able to have a better view of the damage (the uderside of the PCB might also be damaged).
The best of luck!
btw: isn't it a she? :-D