Have you tried the TV without the ArcadeVGA card and just a normal PC video card?
No, but I think I will try that... use the 15kHz app that's on these forums... good point... I didn't think to try that.
Am I crazy for wanting to go purist?
No
Thanks ahofle.... it's not insanity if other people also want purity

Once you go purist, you never go back. 
I assume that you have checked, and rechecked the wiring on the scart connector. That aside here are some things to think about:
- Does the Arcadevga not output separate syncs, while the scart connector requires a composite sync? If so, the syncs from the Arcadevga would need to be twisted together.
- Does the Arcadevga put out a strong enough signal for your TV to see/sync to? Could a video amp be required.
- Do you have any RGB equiptment (aka real Arcade games, DVD players......), that you can try out as well and see if they work?
Hopefully something works out for you.
1. Syncs were wired together. SCART connection was checked, rechecked, and rechecked again (over and over, I may add). We had the old CRO out checking waveforms on each pin to confirm the connector was good.
2. Yes, the ArcadeVGA signal is strong enough for the TV to pick up. We saw a picture but it was in five bands, which means we were 250Hz out....
3. Sadly, no, no other RGB equipment to test the tv with.
At this stage, I am going to try the tv with the on-board VGA port with the software to drive it down to 15kHz... will post results on here shortly enough.
Thanks for the input guys!