placing objects on a tunnel chainage

I need to place objects on a tunnel chainage (centreline) which is curving in plan and in the vertical (like a snake)

The objects need to be perpendicular in both directions

So far I have been able to place the cells at the correct distance but I haven't been able to get them to place perpendicular in both directions (plan and vertical)

the workaround I have used for the moment was to include a cross hair which I rotate the cell and snap to the chainage line

is there a more efficient way of doing this?