1964 truck motor mounts

[wellabee]

I recently put a 80 c10 front end in my 64 c10 and when trying to use the motor mount brackets out of the 80 c10, the lower bolt holes line up with the cross member but the top of the motor mount bracket ( where it bolts to the top of the truck frame) is about an inch above the 64 c10 truck frame. I am a first timer here any suggestions or did I do something wrong