I bought a pair of them from my local Toyota dealer, the part number was right on the money and despite the scorn the parts guy gave for the MR2 when he was asking what they where for. It took me about 5 min and a flat head screwdriver to replace. They cost me less then $2.50 each and I was happy, no more rattling prop rod from my engine bay.
Side note: I've seen it both ways also and really don't know.

Something tells me the FSM doesn't mind how we have it as long as we have it.
