I say stick to 225/45/17 all round or go 235/40/17 at the back only.
Bear in mind that 225/40/17 is an odd size so expect to pay more than for a 225/45/17.
205/40/17 is definitely a no go for 8J. That tyre size is more in line with 6.5J to 7.5J at a stretch. That tyre size I'd for Polo's, Toyotas, Golf 1's, etc. :cartel: