Other than the hardware they come with, they look the same to me. Same part number other than the suffix.
View attachment 1715451855
It looks like you used the the flathead machiune screws which were intended for the countersunk inner pattern.
I think the only way this works is to use a allen heads or similar.
Hard to tell from the Speedway photo, but looks like that's the difference in the two kits.
You may have time to stop by a hardware store and buy four this afternoon. Just check the depth so there is enough threads to hold well but noit so long as to bottom out when tightened.
View attachment 1715451854
