I have the pot off my '79. I just finished cleaning it and the head externally. I cleaned up the cylinder wall also and it is very smooth. I was thinking it may need some roughing up before I re-install it. The first question...is the cylinder liner on a '79 nikasil/ceramic or good old steel/iron? The second question...would it be sufficient to rough up the cylinder with some fine crocus cloth (assuming the cylinder is steel/iron) or should I buy the drill attachment stones that are used by mechanics? Third question...is there a recommended chemical to remove carbon from the head etc?