Rear Control Arm Bushing Size

It's time to change the rear control arms bushings on our '91 Pontiac Trans Sport.

I've found the parts on autozone.com - Rare Parts / Part no. 16199-2K55 but I have a slight suspicion that this is different from the original part.

Does anyone have the GM Service Manual specifications and size of the original control arms bushings so we can check before we take the rear suspension off?

Thank you!