Back three plugs are best accessed with the engine tilted forward as much as you can get it. There are tools out there to assist with that, and Ive seen and used a rachet strap to do this to get maximum tilt.
I dont know much about the PRJ wires, but when I installed the MSD wires I used the stock heat shields until I can get a complete set of the fiberglass socks.
I would not jack up the motor or should not need to, particularly by the oil pan. If you are doing a tune up, might as well replace the PCV valve. Id go ahead and check the belts as well and make sure they are good. Thats about all I can think of at the moment.
