I'm not 100% sure about this info, but I just finished putting the MV Corse frame protectors on my Brute. The 55-60 nm is for the 14mm bolt that holds the engine to the frame. I tightened the smaller screw up to 20 nm. I couldnt find definitive specs, and as always use some loctite. The only thing I wanted to add was that at 20 nm, the screw felt extremely tight and also cracked/flaked off some of the paint on the frame. Kinda what I was trying to avoid in the first place by putting the thing on there.
Sorry about your paint coming off. I was afraid that might happen so what i did was go to the auto parts store and picked up some thin o rings put them on the frame protectors then blue lock tight just snuged them down no need to torque the outside bolts they are just holding the frame protectors. Now the locktight should hold them in. Plus the the black o ring brings them out a little farther. as long as they dont loosen they will do there job in case the bike falls over.