Hi. Thanks for using JA! I will try and help you out.
Could you get me the engine serial number please?
Thanks for the information.
You will first need to rotate the engine and insert the 8S2291 timing pin into the fuel system. This way your engine will be on TDC and so will the pump.
Then you will need to remove the timing advance cover and timing advance.
Then remove the fuel transfer pump and tach drive.
After the timing advance is removed, you will see 4 bolts that hold the drive group to the front covers plate. Remove the bolts and the drive group will come off. After it is off you will be able to remove the shaft from the housing and replace. The shaft will have a bearing and 2 O rings on it. Since you are replacing the shaft, I would recommend replacing the bearing as well. Also the I rings of course.
Please let me know if you need more help or have more questions.