<img src="/forums/images/graemlins/drunk.gif" alt="" /> What I like to do under circumstances like this is to:
1. I would take fine sand paper in HAND and lightly scratch the surface of the cylinder wall in a circular/up and down motion.
2. Then I would scrape the surface of the block and clean it with carb cleaner, I would clean the cylinder with a cleaner soaked rag.
3. Now I would lube the cylinder.
4. The piston should have printed on it how much oversize it is if at all. A complete set of rings should be installedon the one piston. I would choose cast iron for this job.
5. Relube the piston and the cylinder and install the piston/rod.
6. Reclean with carb cleaner the block and head. I would NEVER use any type of sealer here.
7. Install the head making sure everything is DRY and very correctly lined up.

I am not aware of the length of the push rods needed for this mod. If it calls for the length you have...use them!
If there is no ridge I would have sanded a little more on the carbon buildup and it would no longer be there. I would not go for the ridgereamer... Not for fixing this problem.
Big Jim