I have the Quickjack 3500, same as someone up above. It fits the once you figure out where to position the two sides to get the right place for balancing the car once raised.
So it fits the Speedster and I have also used in on a Subaru Outback and Nissan Rogue but found that it was too short for a Porsche 996. For that you'll need the longer QJ 5000.
@Alan Merklin had a really nice 48" scissors jack that came from an older SOC member who sold his Speedster. It was a Bend Pack LR-60. It was slightly higher quality overall than those from Harbor Freight and we all know how much Alan has used it on his builds with no issues. Here's the SOC write-up for it: