Roger,
I woukd not recommend removing the hinge and separating the leaves. The two end stops (inside the hinge) are to keep the leaves correctly aligned. They can be fiddly to access and sometimes difficult to reset.
I sugest:
Undo the two stay arms by removing the pins at the bonnet end of each . Make sure the loose stays cannot short out on the battery.
Remove the slotted screws holding the front and rear hinge end plates.
Ensure both catches on one side of the bonnet are engaged and place a suitable large piece of cloth on top of that bonnet half. I usually use a clean blanket.
Fold the other half of the bonnet on top of the cloth, ensure the cloth protects the halves from touching one another.
Prepare an area to put the bonnet once removed.
Stand at the side and release the two catches.
Take the lower rear handle in one hand and lean over to hold the front end of the hinge with the other hand.
Lift the bonnet clear taking care to avoid the headlamp and place it in the prepared area.
Before replacing the bonnet, cover the scuttle and top of the grille with cloth which can be removed once the leaves are nicely aligned then reverse the removal process.
It is a knack made easy with practice but I can assure you it works equally well for the wider bodied cars and I have even managed to remove and replace the 6 bonnet alone but the additional length and extra weight make that one much more tricky.
B….
Roger Grix
Bernie