I believe it's mechanical, and on the opposite side of the head from the distributor (passenger side).
Yeah if its carbed, passenger side immediately in front of the thermostat housing. If its fuel injection, its in the gas tank.
See attached picture, this is my motor 22R (1982 carb) and it the the round silver looking unit directly to the left of the 22R sticker and to the right (next to) the upper radiator hose http://viewmorepics.myspace.com/ind...dID=403890559&albumID=545061&imageID=22814057 Hope this helps you out.