I'm in the process of rebuilding an ST1 that ran for a short time with low oil.  The two main crankshaft bearings show signs of damage, but the crank journals look good with no damage.  The crankshaft rod journal bearing has more damage and the crank has some discoloration.  I can't feel any damage to the crank surface, but I'm wondering if I need to do something to clean the surface of crank journal?  With the tools I have I can't accurately measure the crank to determine if it is out of round.  Thoughts?

Also, I have a parts and shop manual for the engine.  Is there an operator's manual available for this engine?

Thanks in advance for comments and advice.