I wanted to take a moment to update this thread, for any future readers. I am using terms that should be accurate for any future searches.
While I investigated several options, here is a summary of what I eventually ended up with.
All work on forks was completed by Traxxion Dynamics, in Woodstock, GA (USA).
* I had bought a set of '04 or '05 forks from a private seller, for the gold tubes and radial caliper mounts. Traxxion deemed the inner and outer tubes to be bent, so they were unusable.
* My OEM 2002 silver forks were sent to Traxxion and disassembled to recover the silver outer tubes, which were straight.
* The 04-05 gold forks were disassembled to recover the axle clamps with radial caliper mounts.
* New chrome inner tubes were purchased from distributor Brook Suspension, in the UK. They are Tarozzi brand, from Italy.
* Silver outer tubes were sent for anodizing to gold color. Traxxion was not satisfied with first attempt, so a 2nd attempt was done. 2nd attempt did not match OEM gold ('04-'06), but I didn't press for more attempts. Not sure if the anodizer used a different color, or the original silver had any impact. By comparison, the OEM color is more translucent, shinier, and a bit more orange. See my photo.
* This mix of inner tubes, outer tubes and axle clamps were rebuilt with new seals and Traxxion's AK-20 springs and cartridges set. The AK-20 should be one of the best fork upgrades available.
I have successfully mounted the forks on my bike. However, when attempting to mount the right caliper, a Brembo M4 monoblock, there was some kind of interference between the hole and bolt which resulted in the upper / outer half of the threads being stripped. I have decided to use a Helicoil kit to repair the M10x1.25 threads. The total depth of the hole is about 28mm, so I am going to insert a 20mm long Helicoil. I will have to use a series of clearance drills and try my best to keep the drills and tap concentric with the original hole.
I am using my OEM 320mm diameter rotors. The original question was, which offset spacers would I need. I found one other reference that 10mm spacers were required, which is standard for the Nissins also, but the owner chose 7 or 8mm spacers. I bought 8 and 10mm spacers to try both. It turns out that both 8mm and 10mm would work, with each biased to the inner and outer range of the service faces. I chose the 10mm, which gives 2mm more of a torque arm for slightly stronger braking.
I plan to repair the hole tonight, mount the caliper, and bleed the fronts.
My final set up will be:
2002 ZX12R
Custom forks with '04-'05 axle clamps with radial caliper mounts
Traxxion Dynamics AK-20 springs and cartridges
Brembo M4 108mm monoblock calipers and pads
Brembo 19RCS master cylinder with lever and reservoir, which has the 18mm or 20mm lever pivot distance
320mm OEM rotors left over from my 2002, with remaining service thickness
10mm spacers
I prefer new rotors, but the pads seem to be placed properly in the existing worn rotor faces, and I wasn't ready to spend even more money.
Finally, I wanted to say that all my communication with Traxxion Dynamics was with Dan Anderson, who was superbly engaged at all times, with interday replies. He provided me with great clarity on their processes, prices, and helped me work through my strategies after they determined the original '04-'05 set I sent them was bent. I had previously considered using Race Tech, but I did not find them to be as helpful or as clear. I had originally found Traxxion because of the set up videos their owner, Max McAllister, presents on YouTube.
I have high expectations once I hit the road, hopefully by the end of the month. I will post pics of my fully renovated bike once I receive my Marchesini wheels, which is another drama told elsewhere. Ordered in February, may not arrive until the end of July or later...?
Thanks