Do you have the 1 5/8 dies now.. if so just lay in a
piece of 1/16" sheet metal and bent a piece of 1 1/2
scrap.. it will shape the sheet metal and fit the 1 1/2...
I used a 1 1/2 piece of galvanized scrap and layed it
in there and gave it a couple of wacks with a BFH
to it would stay centered