Detach bad PCI-X slot to avoid expense of logic board?

Installed a SATA PCI Express card in a dual-2GHz CPU G5 (the very first model - I hate Apple's not naming clear model designations!), went-in flush, felt good tactile-wise, but about a couple of minutes after reboot, the Mac's power cut out, presumably from a circuit breaker, and thick smoke was pouring out of the fan vent. Removed the card, and the frontmost (toward the connector) of the two slot tabs was burned to a crisp, and the Mac's slot was melted.

Even with the card removed, the smoke again immediately began blowing out when attempting to power-up the Mac, and the circuit breaker kept tripping immediately, so we of course promptly pulled the plug.

Our question is, our AppleCare is kaput, can't afford a full logic board replacement right now (just bought a MacBook Pro), but we strongly suspect that the rest of the logic board may be just fine, so would it be possible to send-in the Mac to a third-party repair firm, have the technician "surgically excise" the burned PCI slot, then see if it still otherwise passes the logic board hardware test?

Even if they're not set-up to do multi-layer board-level repair, would it be feasible to, I mean, even take an X-acto knife to sever the leads to the bad slot? We could live with sacrificing one of the three slots to save many hundred dollars!