Another tire fitment question – ’68 Fury Suburban

Hi Guys,
I'm the newest owner of a '68 Plymouth Suburban, very nice and original. Will bring the car to Brazil on the next weeks.
For the Suburgan, will the rear 15x8 wheels with 4,5" backspace and 275/60-15 tires fit with no problems?
Or maybe I should consider 235/70-15? I like tires with more rubber on the back, for a better side look.
Front would be something like 215 or 225/70-15 with 7" wheels. Magnum wheels all the way.

thanks
Author: JAmes Dodge