235 70 15 rear early abody

Its about 1/4" difference fronts would be 5.9" and rear sidewall is 5.6"

I can see it now....
Driving down the road at 45 MPH and a dude runs up and says "Man, your rear tire is 3 tenths shorter than your fronts". ;)

For years I ran a 255/70 15 on front and 275/60 15 on the rear of my 78 LRT and no one said anything. Its what I had and from 20 feet away it looked ok.