This is a very cool board (that's a blatant suck-up but it's true). I had no idea there are people doing this level of modification.
I went another route, one which won't work for many people but is life changing for anyone who can use it. Also, it's damned cheap compared any commercial power chair. $2,600 to build, does 20 mph for 40 miles and goes places unimaginable to most power chair users. Before getting upset about a link to a personal web page, let me say... I don't sell anything... my site doesn't even have contact info... it's only there to help people in need. This chair provides better mobility than a bicycle and takes very little to build.
http://www.garyrin.com/wheelchair/Sun/E ... cycle.html
Here's a video. 20 mph on a bike path at the park, turn 90 degrees into a field without slowing down, up a steep hill and three 90 degree turns into the bathroom.
https://www.youtube.com/watch?v=AdHk8qG ... e=youtu.be
If you can get groceries in a manual chair then this would likely work for you. I don't even drive anymore. I put 1,300 miles on it in the last six weeks. Library, mall, grocery store, park, and tho I'm ashamed to admit it, I even take it to Walmart. I have a major improvement in the works and I'm interested in comments...
Gary