Just to clarify for future reference, having gone through all of this recently due do the previous owner of my car loosing all of the bolts and spacers.
Spacer: OD=12mm / ID=6.5mm / THICKNESS=5mm (measurements taken from new Nissan P/N 13525-58S00)
Bolt: 6mm dia. / 1mm pitch / 15mm length.
I'm using some OEM 25mm bolts with the integrated lock washer and flat washer (common mounting bolts for things in the engine bay), which leaves me with 22mm of exposed thread. When installed into the CAS I can see 2-3mm protruding towards the cam gear, but there's 15-20mm of clearance before it hits the cam gear.
Cheers