i did not put seafoam but i put a oil treatment(its thick like honey)
now i have no more knocking and it runs great.
it also makes my oil pressure higher, wich i think is a great thing...

 

sounds like lucas oil stabilizer, also sounds like you did some damage running it with the internal leak

make sure you buy the good gaskets (felpro's)

but honestly, if i was ready to drop $1000 on a knocking motor, id consider replacing it.