models with better gear ratios

[Sovereign]

I'd like to eventually change the rear end on my 86 to a better gear ratio. I don't care if it's posi but that's a bonus for sure. I'm just wanting something around 3.23 to 3.50 so it works better with an overdrive transmission and is a direct swap. I have a listing of all the codes that the rear ends were stamped with at the factory. However, is there any particular year range or models that typically had the better rear end ratios, or do I just have to check every truck I come across? Would prefer to stay with the 10 bolt to save money. I don't need a 12 bolt.

Thanks