Hi Ian
You have an impressive collection mate
Here's my Venom tuned 35, It's had the O-ring piston seal conversion and is uber smooth
Pic 1
Pic 2
Pic 3
Pic 4
The piston has been sleeved, it's had delrin tophat and guide and shims fitted to the breech to stop the reblue from being scored on cocking
I swapped it for my HW90
Cheers, John