Maxx Products (MPI) has a good glow plug connector that comes
with their on-board glow driver. It is spring-loaded and has a
rubber boot to cover the plug. To attach, you pull on the wire,
which disengages the spring inside the boot, slip it over the plug
and let go of the wire. This locks it onto the serrations on the
plug post. To remove, you again pull on the wire and lift off. While
installed, vibration will not knock off the cord as it takes direct
pulling of the wire to remove the boot. Click on the following link
to see the connector at MPI's website. They sell the connector by
itself with a 20" lead for $5 or the complete remote glow plug
system for $11.50.

http://www.maxxprod.com/mpi-22.htm

Hope this helps.