I replaced to inline filter, the main vacuum booster supply hose, and the 3-way anf 4-way T-fittings today. (The old filter was definitely dirty). Unfortunately not too much improvement overall.

Your description of it driving like a non-turbo may be very descriptive of my problem.

I am not clear on how to test the overboost line. It's a rigid line and I'm afraid I will break it if I try to remove it from the ALDA fitting. Visually it does not appear to be dirty or gunked up in this particular section. It does terminate into a 1" rubber tube before attaching to the firewall (switch), but even reach that 1" rubber may be a challaenge. Anyhow, are there other points or ways to test this? Again, I am pretty sure that the turbo is not working at all :-\

Thanks.