On a properly marked field under NCAA the 60' inbounds spot or line is the inside edge of the hash mark. Check Appendix D.
Now, this is some really fine detail, and I'll bet no one really cares, but you opened the door, counselor. Although neither 1-2-1-k nor Appendix D clearly specify that the hash marks are to be drawn to the inside or outside of 60' line, conventional thinking is, indeed, that the inner edge of the hash mark is on the 60' dimension. However, the hash marks are actually two-dimensional, i.e., in addition to being 24" long, they are 4" wide. Thus, when 7-1-1-b says that "... the ball shall be transferred to the hash mark," that means the ball should be on the hash mark. It doesn't say "...transferred to have the outer edge of the ball in alignment with the inner edge of the hash mark." Also, 8-4-2-b-1 and 8-6-2 specfy that the ball may be located "...on or between the hash marks." "On" means on. It doesn't mean immediately inside. It means on.
OK, so having said all that, in reality, virtually everyone places the ball just to the inside of the hash mark. But they could put it ON the hash mark and be totally correct, by rule. Do the teams care? No. Do they care about 2' of difference, as posed in the original question? Yes.