Series 180??

Thanks for writing in! The coil balance spring you have does appear to be the Series 180. It appears you'll need the S180-7, although, you'll want to be sure that all of your springs are stamped with the number 7.

The compatible coil housing pivot and tandem housing are the 15-087 and 15-086, respectively. 

You'll need to first insert the coils into both of the housing components. Then you'll connect the 15-086 to the top of the 15-087 housing pivot. Once this is completed, you'll need to connect both coils to the 16-024 Mounting bracket.

The entire assembly will need to be put together before installing it into the window.

I hope this helps!

My apologies for the delay in my response and thank you for your patience. In the Series 180 coil assembly, you'll need to use a pair of needle nose pliers to hook the coil springs and bring up 16-024 mounting bracket to the mounting hole. Then you'll be able to screw the bracket with the coil springs to the window track. 

They are not likely to lay flat with the bracket, unless the window manufacturer made clearance for the coil spring.

I hope this helps!