So I am working on my 2006 GT project car. Bought it with a bad engine. The used engine I bought has one broken plug that I have to remove. I have a kit on the way. My question is what is the best spark plug to use so I will not have this happen again. The plugs that came out where not the one piece design. I have read some reviews on the Autolite HT1 and they seem to be okay. When the new plugs arrived, the top strap looks welded. Does someone make a true one piece plug that works in the 4.6?