There is no difference between the threads of the two rally rear derailleurs. Without having the pieces and bike in hand it would be near impossible for us to determine what is going on. So either the threads are damaged on the type 1 or???
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1 Super Record bike, 1 Nuovo Record bike, 1 Pista, 1 Road, 1 Cyclocross/Allrounder, 1 MTB, 1 Touring, 1 Fixed gear