Just going through some old threads and noticed that I never posted an update. Better late than never.
Went with the HG rebuild/highflow option. Stao's service was A1 and the turbo was back in my hands in about a week (Syd-->Melb-->Syd).
The FMIC and plumbing was removed, cleaned, checked for damage, and reassembled. Throttle body also checked and cleaned. All good so far.
Engine was checked for any damage, plugs removed, visual inspection all ok. Looks like the FMIC caught all the busted compressor wheel bits.
Installation of the turbo and oil lines went as expected, left the heatshields off in case I had to go back in later. Removed the standard boost valve and replace the wastegate actuator with an R32 10psi unit.
Also stayed with the factory dump for now. Front pipe back is 3" - 3.25" - 3.5" and I have a 3" bell mouth dump/front to install later if required.
Inspected and cleaned the AFM - this would have been the reason for not being able to maintain idle.
Rechecked all fittings, filled coolant, replaced oil/filter. Rechecked all fittings again - to be sure.
Finished beer, crossed fingers, primed fuel pump and fired it up.
Kicked first go and ran a smooth idle.
That's pretty much it. I've been too busy/lazy to sort out the SAFC so the factory CPU is running 10psi on the standard pump and injectors. Feels stronger all through the rev range but there is a noticable lag (about 500rpm) before boost comes on strong. This was expected due to the highflow and would improve slightly if I install the bellmouth dump, install/tune the SAFC, and adjusted the timing a bit. It's nothing I can't live with.
MADGTS has returned to it's daily duties of getting the kids to school and me to work every day. Still as reliable as I could ever want.
Just kicked over 208,000kms and it's still the best car I've ever owned.
Cheers,
Z