Wild thing wondergears seat question

I am working to continue a couple wild thing builds with my STEAM students via digital conferencing during quarantine. We have improved the rear castor, and built our seat frames. I ordered a couple of seat/harness combinations from Wondergears.com.
https://www.wondergears.com/products/child-secure-seatbelt-vest
Has anyone used these for their builds yet? The website has all the measurements posted online except for the overall width. I am trying to find out how wide the seat is at its widest point.
Thanks for the help!!

I dont know but will ask Andrina Sabet - who I go to for all things ‘seating’!
best, Cole

Thanks! I finally got notice that the seats have shipped but I imagine delivery may be slow right now.

I am curious about how you improved the caster wheel?
Thanks,
Cherrice

I removed the rear castor, created a steel plate, and mounted a heavy duty nylon castor with bearings on the rear. The plastic wheel would often get stuck at an angle and cause the vehicle to veer to the side. Now they track straight even before the addition of the gyro.

Here’s a few shots of the two we made for our LEAP Pre K classes.

Thank you - very helpful!