Boost alloys with 265/75/16 BFG A/T tyres and 30mm spacers

[Fixanything]

Re above subject I have a 1989 defender 90 with rear drums and as part of a facelift project want to fit 16x7 Boost alloys ( I think I have established that they are ET33mm or offset +33mm) and 265/75/16 BFG A/T fitted with -30mm spacers would net out at +3mm. If all correct ?, what I need to know is would they protrude outside the wheel arch/mud spats ? Anybody have this config and does work OK and is it legal ? Many thanks for any confirmation and advice.
Cheers
Mark T