Replacing a ballast on a standard twin starter fluorescent

[Robo]

I've got a few faulty fittings to repair with these ballasts.
currently I'm to sure if the original fitting have individual ballasts or a combined ballast for both lamps. However I think the picture ballast should work.

Im ok with the lamps connection as I think one side of each lap is wired in series from 23 to 24 and the other ends to 21,22 and 25,26.

For the power connection is it live to 3, 2 to earth and 1 to neutral?

any help wold be appreciated

 

[Marvo]

For the power connection is it live to 3, 2 to earth and 1 to neutral?

That's what it shows on the little drawing. Just follow the diagram it should be straight forward.

 

[AndyOz]

Remembering that the starters (if there) are now redundant.