Replacing them isn't very difficult...
Remove the intake, unhook the connector and fish the wiring back, then use a 19mm crow-foot with ratchet to loosen then can unscrew by hand. (I took out the Neutral switch with a wrench and that sucked...get the crow-foot)
Attached the pics, this is on the drivers side of the manual transmission... the cables are a bit in the way, but they moved out of the way enough.
I haven't done the thinner washer ... yet, but it only took about 30 minutes from start to finish.