901 Transmission definitely has a clutch guide tube as part of the assembly (#1). Early 901 has the clutch guide tube held on with two studs/nuts at 12 and 6 o'clock. Later 901 has the two studs at 2 and 8 o'clock. The guide tubes, I believe are the same, but to be sure I'd need a photo of your transmission without the clutch fork/bearing installed.
-Dave