okay, the obvious answer would be that I have the wrong fuel pump...Carquest #4666. Should fit a 1959 261...it is dual-action. Problem is that it won't fully insert into the hole on the side of the block. The lever on the pump appears to intercept the lobe on the cam too soon. What I am left with is a gap of about 3/8". I thought it was the wrong part so I test fit the old pump and it had the same problem. I am doing a complete rebuild on this engine, so it has the new M4F cam from Patrick's...could this be part of the problem?
