Installed it, well, I removed the old crown race for reuse and took my time cleaning/packing the bearings in my CC S2 headset. I measured twice but still managed to cut it a bit long. Back to the shop to generate more black dust...
It cut perfectly square with abrasive wheel spinning at 30,000 RPM while the shaft was slowly rotated. No splintering.
Just as I figured, the steerer IS
pulltruded CF. Do NOT substitute ANY insert as this tube has EXTREMELY low resistance to the stress expanding-type nuts produce. You must use the insert to add torsional and longitudinal shear strength to the steerer. And the gluing process is very critical. You must wet BOTH surfaces and allow the epoxy to fully fill the gap. Putting the insert in rapidly will starve the bottom of the insert of epoxy, resulting in only partial bonding. Not good.
With glue, insert and crown race (15g), the entire fork weighs in at a svelte 354 grams. Contrast with 595 grams for the original and it looks much better. I shall see how it handles
The bike is now 276 grams lighter at a little over 1$ per gram cost!
Darn it, I screwed up and cut it too long. I don't know what happened since I cut it EXACTLY the same length as the one it replaced, including the insert flange thickness. The top cap might be the problem since the insert is smaller inside diameter than the STEEL steeer it replaced. I have 5mm of spacer on it already so it looks like another 4mm is necessary. I have no spacers on hand other than those in use so I think a single 10 mm Douglass will be on order.