My plan was also to use a snorkel air cleaner and make a 340. I actually had a single snorkel as you'd need to do some metalwork to make it work, but come on there are loads of you who can do some metalwork, this should not have been too difficult. Get two oval holes in the right place (might mean welding up what is there) and then bevel the edge. I was going to make a hardwood former or something.

then for about the first time EVER I lucked into a genuine 340 piece for about $40 here in the UK . The lid was shot but I had the spare from the snorkel air cleaner Sweet!