Dave I had the same problem, but on my back up contact switch there was a little screw at the end that contacts the reverse lever.
I screwed it out a little so the lever would stay in contact when you release the shifter
Someone here told me about that when I was doing my back up light mod. I did not see this screw on my 87, but it was on the TOY. Both are 4SP
Here's that old info: https://www.fiero.nl/forum/Archives/Archive-000001/HTML/20000503-2-000918.html
[This message has been edited by DXR_DAD (edited 01-13-2001).]
[This message has been edited by DXR_DAD (edited 01-13-2001).]