Billit Valve Cover Adapters
I have a pair of these I did not use them as I went a different direction.
$30.00 plus shipping
This is a partial description:
Billet aluminum breather adapters, They use a large nut and o-ring to clamp onto your valve cover while firmly holding the breather in place and preventing leaks. Because the nut can easily adjust to nearly any thickness of valve covers, these work just as well with super thick cast aluminum covers as they do with thin sheet aluminum or stamped steel models. The inner diameter (where the breather fits into) also includes double O-rings to assure positive sealing and no leaks. These are designed for 1-7/16" diameter valve cover holes.