Exchanging chip in V7

[fratres]

Thanx seaneyb2003, gives me a good feeling that not everything´s lost. Already thought of selling it, what a shame for a V7. Now I want to exchange the chip and compared the installation diagrams of Crystal, Infinity, Duo2 and Magic 3, and the results: if I don´t need to desolder the now unused wires on the MB , but only insulate their ends, and if different ground connections don´t matter, it´s only a few wires that need to be changed or added:

Crystal: installing SX, TO, 3V3 and changing the W-wire-point
Infinity: installing Y, SX, 3V3 and changing the W-wire-point
Duo2: installing S, PWR, maybe change ground?

My question: could anyone tell me if these installs have different difficulties? Thougt maybe the Y-wire of the Infinity is not too easy? And PWR for Duo2 does not look too easy either. And then the S-wire of the Magic is very close to the SX-wire of Crystal and Infinity, could I leave the wires at their old solder-points? Z-point of Magic 3 also very near to TO-point of Crystal. And finally:
what is about the W-wire? Has a total different point in the Magic 3 install, could I leave it there or do I need to solder the wire to new points?
Sorry for all these detailed questions, but I am lost without help, and for all you pro-installers I hope they should´t be difficult to answer at all. Here is a Magic 3-installation diagram as reference (though not my install and big picture, sorry):

http://www.gamefreax.de/GF_Page/modchips/playstation2/Magic3/v7/Magic3.htm

Thank you so much for any help!!!