Interaction of years of incomplete education with education

I would like to investigate the association between having incomplete education, the current education level and its effect on earning.
I regress this on log earning and control for sector, age etc but i wonder if a simple i.education#c.yrsincmpled is the right approach.
I really need some direction.
Education is categorical..it was coded with arbitrary values...10 to 61 but there are only 20 unique categories. I hope this makes sense. Thanks in advance! Will post results below.