Vapor seperator drain screw F225

[Simon E]

I recently cleaned out a VS on a F225 with water and rust present wich developed from the high pressure fuel pump and a screw .The drain plug is stuck and Ive tried to free it up with no results .If I snap the head off has anyone had any luck tapping and resizing a new one in there ?
Also ther is and oil seal cover which sits on top of the drive shaft housing it is in two pieces a stainless plate and a rubber seal wich make up the part should the stainless plate be on top or the bottom ?

[boats.net]

We haven't had any of drain screws break off but should be able to redrill if you can find a larger drain screw. Not sure what seal you are talking about, take a picture or give a link to parts page that shows which part it is.