A fair number of remanufactured(Python was firm, midamerica the vendor) FI bits recently came on the market for VW's, which is likely quite similar to those used on the 914. Also some new stuff.
For example, this looks like a pretty sweet fuel new german pump
It is air flow controlled, but temperature dependant. Those are old sensors with *****ty wiring, check those too. The club/world has something that will help you. I think you need a test light too.
The shop manual for the Superbeetle has a whole chapter on L jet, complete with a portly bald German gentleman indicating the air cleaner in one photo, which has a dinky little opening for how big it is. The air cleaner, not the guy.