You need to get an appropriate tee and keep the connection before the pump. The return should work if you stay close to the tank. The pressure increase there may still be enough to push fuel through the heater metering pump when not in use or at least throw off the mtered delivery.

Dennis

Sent from my Windows 10 phone

From: Andrew Berg<mailto:andrew@BERGWEB.CA>
Sent: Saturday, July 14, 2018 9:02 PM
To: vanagon@GERRY.VANAGON.COM<mailto:vanagon@GERRY.VANAGON.COM>
Subject: Gas Heater Fuel Connection

On my 84 camper, the tee fitting for the fuel line is immediately after the box filter upstream of the fuel pump. I plan to lose the box filter and upgrade to the larger Bosch post filter. Where should I locate the gas heater tee? After the post filter or on the return side of the gas tank? Where did VW tie in for 86 and later Van's?

Andrew