The hubs for the 1994 Ranger are all the same size factory or after market. The hubs work on any Ranger or Explorer from 91 to 97 (Dana 35 Front Axle).
In 1998 The Ranger went to a different front suspension and to accomplish this switched the front to a vacuum hubs. This style is continued today. That is the difference in the wheels.
If you like the wheels and want to keep them to use, I'd recommend going to the local machine shop and having the machine the centers wider on the lathe. I have no idea what they would charge you.
As for the front hubs, if you have auto locking front hubs you can directly replace them with the same thing. The hub pulls off and you slip the new one on. If you would prefer to switch to the manual locking front hubs, you need different spindle nuts. You can remove these from a manual hub ranger or you can buy a manual locking hub kit from Warn or such. If you want to upgrade, get a set of Warn hubs from the TRS Fab and Offroad. These are superior to any other hubs for the Dana 35. This should help you
http://www.trsfabandoffroad.com/products/warnhubs.htm.
If you need manual locking hubs, I have a couple used ones I can sell you. I can take $50 for a pair including shipping.
I also have pictures on disassembling the manual hubs if you'd like to try cleaning your old ones and replacing the bearings.
You have several options, PM if you have any questions.
