Personally I think its a huge pain in the ass. The drivers side is defenitly do-able in your drive-way but the passanger side is the big problem. I gave up when I tried
If you have plenty of time one weekend Its possible to do with a buddy. Make sure the front end is off the ground enough to be under it. You'll need to be on the top & bottom of the car for it to possibly work. Just be patient especially on the last ones closest to the firewall.
Currently Im running NGKTR55's & Taylor 8.8 Wires and soon to have an MSD Opti. I was pretty pleased with it after I payed someone to install the plugs & wires.