The plastic piece molded into the air box broke off and is long gone. I need to install a substitute. Found a thread on one of the other P-car sites where a guy attached a 'mirror clip' from home depot to the air box w/ 2 screws. The wire clip hooks one it and can then be snapped closed.
Just returned from a Advanced Auto parts and HD trip. I got some JB Weld, but it's not the strongest one specifically for plastic, as that version takes 15 hours to set. The version I bought tonight sets in 15 minutes, but has about 60% of the bind strength of the longer-setting material. I guess I can try it and if locking the clip pulls it off I'll need to resort to short bolts.
No photos. But below is an image from the Rennlisp thread:
