I am having a very difficult time figuring out what size chains I need for my drive and pedal chains for a 1978 Peugeot 103. Apparently nobody has em, and mine are rusted far beyond practical use. They are slightly different sizes, and I dipped them in de-ruster in an attempt to read the size, but all it says is "tm". This is obviously of no help to me. SO, I was hoping someone else went through this same hassle.