Xantos,

I have quite a bit of experience with both the Pegasus and Olympus. Not sure about your first two questions but here are my answers to the other three:

Ray ,
Im setting up a Pegasus in my Kingcat too . Im setting it up for the single channel operation.
I have a few questions:
1. Can one use a metal Kavan type filter instead of the plastic Festo filter supplied with the engine ?
2. Why is the filter suggested on the upstream of the pump(Suction side) in the manual?
3. Can the fuel solenoid be eliminated and replaced by a manual shut off valve?
Yes, the turbine will start and run normally but it's risky. If you fuel up with the manual valve open, fuel will get through the pump and into the engine and you will get a hot start (don't ask me how I know).
4. Does the CTF switch stay connected at all times and in the airframe ? Somewhere in the manual it says it can be removed.
Yes the CTF switch stays connected and I always keep mine plugged in and accessible (pic of my Olympus install below)
5. What lead is the GSU connected to during the start up ?
Telemetry lead

Hope this helps,

Craig