Newbie M880 questions

[fslay0435]

I recently purchased an M880. It's my first military vehicle, and I have enjoyed cleaning on it and fixing odds and ends stuff. Got a couple of quick questions. First, this truck was used in a mud bog at some point in its life, and it has mudgrip tires. However, it appears that they are 16" tires and I've read where the M880 might should have 16.5". In order to verify rim diameter, do I just measure staight across?

I don't want to have a blowout or worse from having the wrong size tires on the truck. thanks in advance

 

[MWMULES]

It, the size should be stamped on the rim. Chances are because 16.5 are $$$ a lot of them got the wheels changed over to 16's by fire dept's or whoever had it before you. Aswayze and I have both gotten 880's with a mix of 16 and 16.5's wheels.