The removal of the end cap (called "Bearing Cap" in the exploded parts diagrams, item #2) was the most difficult part of the Autoprop overhaul for me. The two-peg tool I bought from Brunton was totally inadequate (bent within seconds and became useless). It is my belief that this cap was assembled at the factory with a locking sealant. At any rate, manufacture a 4 peg tool using the dimensions posted by another member in this thread. Those dimensions are correct. The pegs will need to be hardened steel (you can use drill bit shanks).
A SS two pin tool most likely won't work. When the time comes to remove the bearing cap/end caps, heat the cap with a heat gun (you want to loosen any locktite with heat NOT heat damage the metal), apply your tool tightly (two people with gloves so you don't get burned, one to hold the tool in place and one to apply the torque) and turn in an anti-clockwise direction. Note that this is most easily accomplished with the prop on the boat so it is held in place as you apply your torque. My notes are that all threads on the auto prop are right hand threads (clockwise to tighten and anti-clockwise to loosen) EXCEPT FOR THE THREADS OF THE TAB SCREW aka locking nut (item 4, part number H6 TRI-0221) THAT HAS LEFT HAND THREADS.
I have posted in the photos section a series of photos (search "Autoprop" in the photos section" relative to removing the races, the failed peg spanner etc. Located there is my photo of using a socket that I ground down to produce the tool for removing the left hand treaded tab screw (called by me the "locking nut"). I did this out of desperation in Antigua and it worked well but took me several hours with a Dremmel tool and hand files. Unfortunately I didn't make note of the size of the socket I used. Also, in the files section, there are several rather dis-jointed posts that contain tips related to my experience with this overhaul. It is all about the tools!!!
Evidently the Autoprop comes in a model that doesn't have lip seals and has flooded bearings (open to sea-water). My model has lip seals and the bearings are not flooded. My failure was caused by the Autoprop recall when the factory failed to overhaul my prop with seals (the bearings then failed within one season). Once I overhauled it properly it has lasted 10 years. It is still silky smooth with these precautions:
1. I never allow power washing of the Autoprop. A power washer can easily blow water past the lip seals.
2. I religiously lube the Autoprop upon haul out each year.
Good luck with your overhaul and don't hesitate to make/have made your own tools.
Gary S. Silver
s/v Liahona Amel SM 2000 Hull # 335
On the hard for hurricane season in Puerto Del Rey Marina, Puerto Rico