I used a regular boxed end wrench to remove the nuts holding the wiring.
I purchased a ratcheting style boxed end wrench (about $6.00) from Craftsman to remove the glow plugs.
If you decide to buy the ratcheting style wrench, don't get the off-set style as it won't fit into the space on some of the plugs. (I have the 617 engine).
No fuss - No scrapes- No blood on the hands.
Took about an hour or so to do if I remember correctly.