I would like wider back tires and proportional but smaller front tires for my new MAGNUM WHEELS - 17 X 8 (5'' X 4-3/4'' BOLT PATTERN AND 0 OFFSET). I want them to fit with no rubbing or drivability issues. Any recommendations will be appreciated. I have a stock suspension.

 

17x8 is on the wide side for the fronts, but will likely work. You want tires around 26.5" - 27" tall. Unfortunately, most car tires for 17" wheels are smaller than that, especially in the wider sizes. The taller ones are truck tires and you don't want those.

I'd suggest 225/55-17 or 235/50-17 for the front. These are both around 26.5" diameter. Unfortunately, you are limited in the rear. A 275/50-17 would be ideal at about 28" diameter, giving you a little bit of "rubber rake", but no one makes tires in that size.

You can get a 285/40-17, but that's only 26" in diameter. That's a little small on an A-body for my taste unless you plan to lower the car. There will be a lot of daylight in the wheel well. If you wanted to go that way in the back, you can get a 225/50-17 for the front that is also 26" in diameter.