Technical Is there a difference between mercury pistons made untill 1948 and those made from 1949 to 1953?

Suppose I had a set of pistons from a 1948 Mercury with a 3.75" crank.
Can I put them in a 1949 engine with a 4" crank?
I know the bore is the same, and I know that the Mercury crank had a 3.75 stroke until 1948, gaining the famous 4" stroke crank only in 1949.
I also know that when you exchange a ford crank (also 3.75") for a Mercury 4" crank you also have to change the pistons, due to the pin location.
Couldn't find any clues in the existing threads.
Thanks!

 

Look at the Speedway catalogue or VanPelts has a nice parts listing.

 

Nope, can't enterchange them. The pin to top height is different because of the different stroke.