Yes very interesting information. Firt off I know of 2 Case 500's that got fitted with a inline pump and have heard of several others converted. I know have one of them now with a hole in the block.
Have 2 other 500's with rotary pumps, 2 600's, 2 57's, 2 58 with rorary pumps. My 59 has the inline. Last summer I went to a auction where there was a 1959 900B with the inline pump and had a primer pump on it. I however think the hand pump was closer to the pump. Thanks all for all the good information on this post