I ran across something interesting in my travels through the interwebs. Someone has done a d6 conversion of the classic TSR Marvel Super Heroes RPG. The document is 18 pages long and states it is not a complete game. You will need a copy of the D6 Adventures book. It tries to adhere closely to the MSH rules and feel but I can't really comment because I don't have any real experience with MSH.
You can find the d6 MSH and other Open D6 material, including the D6 Adventure book, here.
You can find the d6 MSH and other Open D6 material, including the D6 Adventure book, here.