Not that I have seen. In that setup the vents are still in the bottom of the distributor base. Adding the filter is more preventative, GM had a filter on the vented optisparks too, so I took the same play from their playbook. Mine has the GM LT1 optispark vent kit that was available and inexpensive 15 years ago. What I drew up does the same basic thing. On my L31, I drilled and tapped the vents on the base, added a 90* hose barb fitting to each, 1 line to the OE air intake duct off the air cleaner behind the MAF, 1 line to the vent system and RTVd the cap to the base. The way thebabove system is setup is just easier if running a vented cap anyway. I wanted to make sure idle fueling would not be thrown off when I first did mine and at the time nobody made a vented cap, however I later discovered that it makes practically zero difference even at idle with that tiny orifice in the hose.