Identifying a 16.5 wheel over a 16 inch

[ApacheIvan]

Ok, I don't know if someone just put the wrong tire size on my truck or if someone put 16in rims on the front and 16.5 on the back. The rims look the same. Are there identifying marks on the 16.5 rim? I have the original spare that I think has never been on the truck, it is a 16.5 wheel, the back tires say 9.5x16.5 but the fronts are 245/70/16 or 75Rs, cant remember at the moment but definitely 16in tires. I have read here where that is not a good idea on a 16.5 rim, Tires 9.50/R-16.5LT are a bit more costly, if I already have 16 in rims on the front I may just get 2 more for the back or a set of white ford rims, or I may use the spare rim and just buy one more 16.5 if there are 16s on the front.. ANYWAYS, how do I determine what is going on with the wheels or tires..