It's a dreadful system Peter, so I decided to replace it with some traditional hood catches.
In the above video I was still using one of the original locking pins and releasing it with a run of paracord to replace the awful cable system, laterly I removed that last pin too and the paracord, I now just use the two Triumph Herald hood catches.
The only minor disadvantage is you need to be sat in the car to release my Herald catches, but it's really no inconvenience at all. I just reach behind and the hood is released in a second, when putting the hood up I fit the two header rail catches first as normal and then close the Herald catches while sitting in the car to tension the hood.
The system is super simple and looks period correct, but above all it replaces the dreadful Morgan cable operated bonnet release pin system with something that's completely reliable and effective.