Unless it's for show purposes only, get rid of that split rim. Get a 16" rim off a newer truck, much safer and easier to get tires for.

 

 

You won't even find a shop willing to swap the tire on that wheel. You can get a steel wheel at a junkyard for 15.00 if needed. There is nothing worth saving in the combo you have now. That tire and wheel didn't come from your truck either. See the locating pin holes between the stud holes? That was common on GM at the time.