DUST COVER FOR 727 TRANS,WHAT YEARS FIT MINE

Chrysler used the cover with the access hole till 1974. 1975 they changed to the solid cover because they deleted the drain plug on the converters. Kim
Thanks Kim,I knew someone here would have the answer! I wanted to get the one that would be correct for my car.
I bought a cover yesterday from a local mopar yard,but I need the little inspection cover the goes in the middle. I posted a wanted ad. Hopefully someone here will have one I can buy.
So why did Chrysler get rid of the drain plug on the converter later on?