Hi,

Were the two nuts on the same side of the semit circular channel or were they on opposite sides of the channel. It appears that they were on the same side and spring in between the two but you said in your posting that you first put the first nut on the screw and so it is not very clear if the first nut was on other side of the channel.
Also the washers are on the opposite side of the spring right - meaning if the spring is on one side of the channel the washers are on the other - or one washer is on each side.