If you have a column shift auto like mine, you'll have to figure a way to mount the shift indicator in the bottom of the tach if you want to keep it. From the reaserch I've done, it doesn't look like a tach was available with the column shift.
The speedo cable change was in September of 86. To see if your '87 has the newer cable, look at the bottom of the speedometer face, if it has the letters 'NS', it has the newer style.