I'm not sure what you mean, I took all the plugs out to do the TDC. The 4th Cyclinder plug looks ok to me, the first one though was soaked from coolant, it was the color of oil but didn't smell anything like it, smelled more like coolant so I'm sure it was dirty. How hard is it to replace pistons? Like I said before I'm new to this big of a job so I'm not sure what I'm up against.