Hello all,
 Anyone in the group know how to access the back side of this bolt. I noticed the bolt head not sitting flush to the chain plate while doing a daily inspection on passage. I don’t know if I missed it on previous inspections or when it happened.  See photos. Thank you for any comments. 

I did put a wrench on it and it turned a little, so I believe it is tight  

Chip 
KOA SM #430