Starting Engine Clutch Housing END Seal

Iam working on a 1937 RD4 caterpillar S/N 4g4344. I'am replacing the clutch housing for the starter motor (end broke off) P/N 3B6402.Can some one help me with the part number for the seal that goes "inside" the end where the "O-ring" seal P/N 2A3676 goes. My parts catalog does not show the "inside" seal (or if it does I'am missing it somewhere)

Seems like your referring to the seal shown on the clutch & starter pinion shaft
#2A3688.

That seal is in the picture with the clutch and starter pinion. 2A3688 is the seal.

OLD MAGNET & jmvmopar think you both for your help. I see where I missed it, I was looking at the housing and did not look on the shaft assy. Thanks again for your help. I knew I had to be over looking somethang.

I went to "Mustang/Cat" today and ask for a 2A3688 seal, would you beleave it, they had 5 in stock. The part number has been changed to 3J-4776. I bought two of them for $19.55 (tax included) can't beat that. thanks again for the help.