Glenn,

I finally had to replace my starter on my '68 Z24 (4-spd) about two years ago. I think, under the circumstances, you should consider exchanging the whole starter rather than "piecemealing" it. It should be available 'down there' and would probably be cheaper (from a auto store) than looking for a "nose cone" elsewhere. I wasn't aware that a 4-speed unit would be different than for an automatic.

Bill