Yup, TOZ35s came with five rear blades and five widths of front sight. The rears were all different widths of slot, and had square notches on one side and U notches on the other. We tried every combination possible that let you have "white" bars visible, and even made up VERY skinny fronts. In the end it came down to personal preferences and visual acuity. Eventually we all tended to return to a front that was perceived to be similar size to the bull, and a rear blade that gave clear and distinct whites that were easy to judge as equal. Funny thing that we noticed was that they seemed to be just about the same as on a S&W K-38 or a Bowmar target rib. I did once shoot silhouette-the reduced version for 22 (40 to 200 yards) and as long as you could judge the vertical adjustment needed, irons worked fine.
Dr Jim