Can't remove cooker hood to check transformer - Smeg KSEIV95X

gmm30

Feeling a bit daft, hopefully somebody with a bit of household appliance experience can help.

I have a Smeg cooker hood over an island (it's mounted to the ceiling), model KSEIV95X. None of the lights work, despite having all bulbs changed. I believe the transformer supplying the LV halogen lights will have failed. All I have to do is remove it.

I have the installation manual including exploded diagrams etc. but my installation doesn't seem to be the same. The stainless steel cover for the "chimney" section (i.e. between the glass and the ceiling) is supposed to be telescopic, so you can lift a bit up for access to the workings behind. Mine is in one piece - almost like a square pipe, with no movement at all. It appears that the cover was slipped over the main hood unit which has then been attached to the ceiling brackets some way. But I can't see how to get them off. There are two smallish looking torx-headed screws/bolts right at the top of the fan cavity but they don't look robust enough to hold the full weight of the thing.

Any suggestions very gratefully received!