Grrr, I just did this but forgot what size I used.....but try some of the bolts that hold on the door armrest/trim stuff. On my '83 (non-monopod dash), the screws that hold the armrests on happen to be the same thread size as the steering wheel puller holes. Your '87 has the later interior, right? It might be worth taking out some of the armrest bolts and seeing if they fit the steering wheel.....I don't see any reason for them to go changing hardware around.
The armrest bolts probably won't be long enough, but after verifying size, you can take them to a hardware store and find a match that's longer.
The armrest bolts probably won't be long enough, but after verifying size, you can take them to a hardware store and find a match that's longer.