The tension worked --it was just missing the number dial and the nut. I took the whole thing off the machine easily but the new one won't go on. I even called in my husband to help and we couldn't get it to work. The old one will pop back on easily. I took the number dial and nut off the new one and put it on the old one but it won't stay on --even with opening the post more (it has a groove for that). I wanted to try a regular nut from the workshop but couldn't find one to fit. It's a setback, but I will get the 301 to work-- just not this week.
On the good side, I did clean it up nicely. I tried GoJo Hand Cleaner without pumice as some people had recommended. You can buy it at auto shops. It worked great! Also it didn't have a terrible smell like some cleaners. The 301 has nice clean gleam to it with all the decals still intact (a couple of nicks in the paint though).