Hello from IA

Hi all,
I've been lurking around for the past couple months and feel I should finally introduce myself. I come from a Mopar family - and have really hit the jackpot on my very own first Mopar.
I found a 68 Dart - California Black Plate car. Really gorgeous, mostly original.

We are upgrading the ignition system, new carb and intake, and having the radiator recored. We swapped out the hubs and drums for new disc brakes on the front - and I'm buying 15x7 police wheels w/ 4.125 b.s. - which is where I have a question. From reading on here, it looks like 225/60/15 is the max size I'll be able to get away with on the front. Is that accurate? How about the rears? Can I go up to 265 in the back?

Thanks for any help. This forum has been great as a resource!
Here are some pics of the car. That's me and my brother swapping out the brakes :)
It's going to be a lot of fun!!

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