Can anyone help or give some suggestions? The speedo cable on my 72 Swinger is hosed and I cant seem to find a replacement.

Ive gone to 3 different parts houses and they all list the same part number,(Pioneer CA 3027). The connector that goes to the speedo head is correct on the replacement,but where it screws to the tranny speedo gear its too small. I searched from 1970 -1976 Slant 6 and V8 part numbers and its all the same part number,but it doesnt fit at the tranny.

The tranny I have is a 3 speed(on the column),and Checker has a listing for a 3 and 4 speed cable,but its the same as the part number that doesnt fit(CA 3027)

Is there an adapter I can buy,or do I maybe have the wrong speedo gear installed?

The lady at Autozone told me I could look through thier inventory,but thats like 150 different cables,and knowing my luck I would find the correct ends but the length would be too short.

Can anyone help me on this?