i did a idi to td swap years ago
if i remember right,i retapped the filter pad(oil feed)for standard stuff...
1/4npt i think,or 3/8,i remember there was plenty of meat for retapping the existing metric threads
then i got a fitting that was the correct npt male nipple on 1 side,and 5/16 compression on the other side...
then i took the stock line (8mm,and 8mm=5/16)and cut the orig comp fitting off and used the 5/16 comp fitting
bend the line slightly and voila,you got oil
it was hard to tell it looked like factory