tsiero,

Easier way than removing the injectors and replacing the heat shields is to remove the GP and connect them across the battery and see if they glow a bright orange. This way you have the GP that need replacement already out and you don't disturb the injection system.

To connect across the battery, hold the GP in a ViseGrip by the hex. Touch the screw end of the VG to one post of the battery and use a screwdriver to connect the terminal of the GP to the other battery post.

Be careful when you do this because the good GP get hot.

P E H