This is the plastic cross over pipe that is on the top of the gas tank. Aftermarket but it looks just like the OE one.
Gas Tank Seal Kit for Syncro Vanagon
Syncro Gas Tank Level Sender Retaining Ring
Fuel Tank Sender for Syncro Vanagon 86-91
Syncro Gas Tank Level Sender Seal
Fuel Feed Pipe - Diesel Vanagon NA andTD Filter to Pump 82-87
Grommet for plastic fuel expansion tank in wheel well