What you need to do is get hold of the 2/2003 issue of the Russian magazine "Tankomaster". Sergey Kirsanov has a great article in there which covers 20 (yes, TWENTY!) different variations on T-34 tank hulls from the Model 1939 prototype to the Model 1945 T-34-85 variants.
The article shows that the numbers of bolts vary over the years by factory, time and model of tank being produced.
Cookie Sewell AMPS