Correct wheel offset and a happy front-end

I've been looking at wheels for my Dart... And it seems that people are willing to sell you anything close. What I want to know is, what is the correct offset?
I want to go with either 14 or 15x6 for the front.
I've got OEM 14" rallyes on it now, I think they're 5.5"... IIRC backspace is like 3-3/8 or 3-1/2.
I'm thinking my front end will be happiest with the offset being where Mopar wanted it, not plus or minus what somebody has in stock...
Of course out back is a whole 'nother story, but that can easily be figured out with a straight edge and scale.
Car info: 70 Dart,73 front end w/disc brakes. Will be skinnies like 195/70s.

Thanks Guys :prayer: