does any one no of an alternative smaller version as the original seems to foul the tunnel

Not certain about IVA if that's applicable to you, but you didn't need a reverse light for SVA and you definitely don't for MoT either. My approach was to remove the switch and save the hassle and cost of fitting a reverse light.

Reversing lamp is now mandatory but can be operated by a dash switch with tell tale warning light.

no not needed for mot /sva, the lights are fitted to the car but not wired up so thought i mite as well

as dusty says, switch on the dash with a tell tale warning lamp will do for IVA