Thanks for the responses.
Yep, a lower offset would've been easier to fit, but alas I already have the wheel and it's +45
Have camber plates at the front, but I've got my left and right struts swapped around and I'm using the plates to get more castor.
On the rears just have Whiteline camber bolts.
Yes, ideally would prefer to avoid the spacer. I guess if I already bought the tyres and there was no physical way they would fit, I may be OK with a 3mm spacer - but only if I was stuck and couldn't prevent that.
I'll put the rim onto the car and take a pic of how much room there is there.