It is beneath the car on the front passenger side about even with the wheel, the fuel filter is also there.
33 Mpg
There was no 1969 "super beetle" only the standard. And which line are you replacing the hard line or the flex line?
Attached to the fuel pump under the gas tank.
I believe it's about 2 to 3 psi.
3.5mm
No, one is a "HOT" wire.
This model uses an electric pump that is mounted under the vehicle. Should be pretty obvious.
It's located near the right rear tire, next to the fuel pump.
It's under the car, on the driver's side (left side) in front of the fuel tank.
http://www.thesamba.com/vw/archives/info/wiringt1.php 3rd from bottom FI Super 76-79
The beetle is a fuel efficient car. 25 in the city and 32 on the highway makes is fuel efficient.