So I had bought the pcv puck for my ALH , but then thought I'd try to hack it into the old IDI .
The brass T is just a 3/4" pex fitting from hardware store. The long 3/4" hose is fuel hose from Oreilly's

I used 2 rubber 90's that are for the old mercedes diesels valve cover pcv system.

https://www.autohausaz.com/pn/6170160281
The MK4 ALH pcv puck https://www.autohausaz.com/pn/028129101E
And here's where it gets weird, the sizes don't match up great so I just winged it.
The 3/4 hose joins up to the intake with just a small metal pipe from something laying around
pretty easy

Where the rubber elbow fits to the bottom of the puck it's too tight but I jammed it on anyway.
Not ideal, probably the weak link. Good idea to have a spare one if that thing breaks or, better yet, find something that is stronger and fits better.
Edit: I'm thinking THIS elbow would work better to connect the puck to the valve cover https://www.hansautoparts.com/06B103221GHose.aspx

And where the puck goes into the brass T I had to heat things up, literally.
The tube on the puck was too small so I softened it up a little with a lighter. To make sure it sealed I put a wrap of silicone tape on the brass fitting - when I jammed it on there it became solidly stuck in place - no hose clamp needed.

If you're wondering where the 3/4 hose is coming from, it's where the old style vacuum pump vented into the crankcase

The puck and the hoses are easily moved out the way If you need to take the valve cover off.