I installed the Panasonic Tail-Up Saddle Light NSSS046 on my mk1, which is slightly different from the one mentioned above.
As explained in the newer STRiDA manual, I removed the original saddle by loosening the bolts and nuts with a 13mm wrench and spreading them apart with a screwdriver, then I was able to install it easily by following the reverse procedure.
The plastic cover at the bottom of the tip, which I was concerned about in my diary like post, was attached without needing to be removed. It looks like the The saddle position seems to be a little high up in the front, but I didn’t feel any pain in my groin even after riding for just under 10km.
It’s wide (total width 210mm, front to back length 255mm) and has a raised rear end, so your butt is less likely to shift out of position, and thanks to the soft material and the rubber damper under the saddle that acts as a spring, I didn’t feel any pain even after during this amount of touring.
Although I am concerned about the following points mentioned in the quote below and the silhouette which may look a bit unfashionable, it is a good product. 
I hope this information will be helpful for you to find a comfortable STRiDA saddle. Cheers,
Doranine