M/T valve cover question

One of the other options I thought about last night was making a conversion part that pops into the larger grommet and the pcv sits in almost like the 66 Commando 273 has on the valve cover. - Looks like a small breather but is actually a pcv assembly.

Making it out of an old breather is the start I guess. I was hoping with this thread that somebody out there had used a set of these valve covers and could show me what they did to make them work- besides welding in a piece of aluminum and starting fresh which may be my only option.
Joe