4500
You didn't say what you were doing with the transmission ,but the v10 will also shake off the 5 th gear nut. .
Simple fix or Insurance to retain said nut remove tail cover and with a center punch min 8 time's around the diam of the nut stake nut threads to shaft. (Drive the the nut threads down into the shaft threads) Heavy hammer (3 lb)and put your arm in to it.