My first REAL SCARE with the Boxster! need some advice..

[Nmbrsix]

The metal shavings in the oil would worry me. Greatly.

I don't know how you can tear the motor down enough to sufficiently flush all of the complex network of oil passages clean, much less rebuild anything, for $4000.

For that $, I think I'd start with a known good 3.2L motor from an S and do the necessary upgrades to that while it's out of the car--cam chains/adjusters/ramps, AOS, water pump, IMS, RMS, etc. That would likely run ~$10k at a minimum...