The PCV valve included in Casco's Tbird road draft conversion kit will not seat, thereby causing a vacuum leak. Casco recommends using a socket and extension to "pound down the valley under the road draft hole." Although this might work, I know the valley pan is prone to leak; deforming the pan by pounding on it might not be a good idea. 

Is there a pcv valve that will properly fit in place of the road draft tube, without pounding on the valley pan?

Thanks

P.S. I think Casco's solution is to insert the socket into the hole and expand the baffle on the underside of the valley pan by pounding on it, thereby providing additional clearance. They weren't clear, but nothing else makes sense.