Getting out a stuck relay - help

[Barreti]

Morning chaps,

The interior light relay on the Griff stopped working ages ago and I've finally got a replacement relay but can't get the old one out.
It's in a tight spot at the top of the fuse box in the passenger footwell and though I can get my hand to it the outer casing is pulling off rather than the relay coming out.

Does anyone have tips for getting it out, I'm fresh out of ideas.