I'm thinking that I need to replace the CCU in my '79 300D (from another thread)...after calling the local wrecking yard, they have one in a '78 300D. Are these identical and therefore interchangeable?

(BTW: my '79 is kind of weird: it is a '79 model but listed as a '78 as it was assembled in Dec of '78 - per the previous owner)

Thanks -Harv