The pics, though big enough are a weeeeee bit fuzzy, and lack lighting - at least on this monitor to give an accurate grade.
Lighting is one of the hardest things to master. A different intensity can be required for different grades and qualities of the coin, from toned, circulated, brilliant uncirculated, proofs and everythin in between.
Typically a MS-62 should have a significant amount of bag marks and damage on the fields as well as on Lincoln, and on thefields and on the memorial on the reverse. A 58 is really close to UNC, only 2 points. That should show the slightest of wear, but..... can be confused with a really weak strike. I can see an Au 58 if things like fingerprints and "most" of the mint luster being gone, while showing hardly any wear might suffice.
I typically use a 3rd party grading service definition to get close to the grade. I then double chck it myself by starting the coin out at ms-70, and subtracting one point from each area that I feel is detracting from the appearance of the coin. Generally apppearance plays a big part in the grading when I see coins graded by the third party grading service. I am sure they have a plus-points and minus-points card they can go by for an easy reference.
Having an keen eye to grade coins is a great attribute to have. When purchasing raw coins, or even one that have been graded/attributed/slabbed will allow you to haggle prices should the raw coin be graded "slightly higher than I anticipated" , or in respect to grading the coin and not the
TPG holder and paper will allow you to get what your paying for.
Good luck on all future grading efforts !