Hi and welcome to FRF!
Suggest that you start posting your questions in the Hybrid/Expandable section of the Forum.
There's a Roo/Shamrock sub-forum there.
As a former hybrid owner, I have to tell you that finding specific information for a 17 year old Shamrock 21 hybrid might be difficult.
Providing pics of what you're asking about, will be helpful.
Dan-Retired California Firefighter/EMT
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing a 2014 Ford F150 SCREW XTR 4x4 3.5 Ecoboost w/Max Tow Package
4pt Equal-i-zer WDH and 1828lbs of payload capacity