Im sorry, I know some may not agree but this scaremongering over tyres is ridiculous. Matched tyres are the ideal solution, but changing a 452 for a 453 is barely going to be noticeable, never mind steer you off the road. Ive driven in all sorts of conditions on all sorts of tyres and not once has a mismatch of grip been the reason for me going off the grey bit, and I dont know anyone or anywhere that is quite as paranoid as here about it - no-one on SXOC has even mentioned it in 12 years ........
Without being funny if you are worrying to that extent Id advise only driving the car when its bone dry, over 10C and Id also suggest keeping below 50mph just to be sure
I totally agree, I was just suggesting an option if he wanted to keep the fronts and rears matched. You're far more likely to crash / lose control through bad driving than mis-matched tyres.