Yeah i understand what you are saying and what you are trying to do and i have already created soldering guides for the original spiderchip at my website www.HackDaBox.com but 99% of people that buy a Spiderchip or Spider GX can't solder at all so this is not an option for them. After all they could buy a cheap chip that works 500% better for a fraction of the price if they could solder !
The idea of removeing the pogo pins and clearing the lpc holes of solder is a great one ( if you can solder ) but what you should do is solder in a Male Pinheader now and then solder the Spider GX to that !
If you have a V1.0 - V1.5 this setup will be very good. If you have a V1.6 then you could still have alot of trouble due to the vias being full of laquer in the xbox motherboard so i go for a LPC rebuild using wires rather than the SpiderWire PCB for the V1.6's !
But this is all too much soldering for a non solder chip and far too expensive ( chip , pin header , solder , wire , Lot s of time )
HackDaBox !