I think an 87 is like the 86.

Does it have 2 heater hoses, 2 air hoses and an electrical connector?

If so, an 89 won't work.


If it is as described, it may just be the electric wires and connector which you should be able to fix.

Use jumper wires to connect battery positive and ground directly to it and see if it works.  (take the front plastic off to see what's happening with the bimetallic strip inside)


Next step is to take it apart (not just the front cover) and see if it's fixable.