I've been sailing the 5.0 for a couple years and have gotten plenty of chances to try righting it solo or with a non-helpful crew (eg one of my kids). What have I learned?
1. Sealing the mast (silicone around all the fittings) to prevent turtling is absolutely essential. Since doing this, I've never needed assistance in righting the boat.
2. Positioning the boat is critical--I try to get the bows and mast each pointed 45 degrees from the wind (so the wind is pointing right at the mast step. Take as much time as necessary to get the boat into this position. Don't bother trying to right it in any other orientation (unless there is no wind--of course hopefully you wouldn't be capsized then). Also, make sure your sails are uncleated.
3. I use a non-stretch righting line tied to the dolphin striker that I flip up and over the hull. **The lack of daggerboards make it much harder to get good leverage.** I'm 180lbs and can right the 5.0 solo but with considerable athletic effort. Also, I've found it much easier to right rigged uni (main only) than rigged sloop. So if the breeze is up, consider sailing without the jib. The 5.0 sails reasonably well uni. I have an aversion to riveting extra items onto the boat if I can avoid it, so I'm sticking with the line-only system.
4. I emailed Gary once about the solo right and he told me it wouldn't work on the 5.0
5. Ed Norris who writes on this forum has installed a pole righting system on his 5.0, but I haven't heard how it works. If you can't climb out to the end of the pole, I doubt you'll get much benefit. Not having daggerboards does make it harder!
Good luck.