Ok I got the part
but the part number was actually D1ZA-3C511-AB, I could not find the exact D0AZ-3C511-E Both fit Windsor...
this part will serve a 302 Windsor or a 351 Windsor. mine is the 302 2v and its totally perfect fit..
also note some of the parts come with a longer adjustment slot and some with a shorter, mine has the shorter slot but is fine... so all that worry about the longer vs smaller slot seems unnecessary, just be sure its Windsor vs Cleveland that you get right..
see photos and thanks again for all your help....
oh and any questions please ask.. I really learnt this tiny piece of the puzzle...