Track blew out of my 1976 ex 340, its a 116 x 15 2.52 pitch 46 qty. I can get a 121 x15 track reasonable. How hard would it be to install a 121 in that sled?
Here is a picture of the front mount location for my 121 suspension in my 77 Exciter known as Frankensled. Look at the other pics of the suspension in the album. Here is a link to the album.