Nice write-up, speedygp — that matches what others have found doing the same job. One thing that might save you the O-ring guessing next time: the sizes are known and documented on the forum.
From previous threads on these exact pipes:
- The 4 O-rings where the steel pipes push into the heads are 13mm ID × 2.5mm, regular round section, available from any seal supplier.
- The 2 O-rings on the pipe between the two alloy caps at the base of the vee are 21.9mm ID × 2.3mm.
The pipes are a push fit onto two O-rings each — penetrating fluid and gentle wiggling with a soft-face mallet gets them moving, so hopefully no need for the plastic-hose spacer and silastic next time. Fair play for making it seal on attempt three though. 
References:
- VF1000.com: vf1000fe seals for water pipes on back of block?
- VF1000.com: Cooling System Water Pipes
- VF1000.com: Water pipe removal HELP
VF Bob 