ask and you shall receive!
Even when asking for the most elusive part, AFTER asking for advice based on symptoms.....
Can't find thread I was gonna post in (@LAMBCRUSHER, thread with 'I'll try to be brief') and since this one is active.....
Had an issue with freshly rebuilt H55F that baffled both myself (pretty easy) and local Cruiser enthusiast/differential tech (who had rebuilt many early, but first H55F), with symptoms indicating it was stuck in two gears, at once.
Long story short (@LAMBCRUSHER, hence the

in the other thread, considering author) wound up that, during the rebuild the top cover was moved, 5th/reverse rail in just the right position at a precise moment, and the indexing pin fell out.
Local'd narrowed down to top plate (before discovering the missing pin), but pinged Georg for his take, along with querying about top plate availability, and this is the reply received:
Home sick, yet willing to discuss my predicament, not only offering advice, but a top plate to use to correct, THEN expediting shipping to get her back on the road.
I am not worthy......