Hi Russell,
I am so glad you wrote with this feedback, thank you. Indeed, we include the link to the instructions for install on the website with the e-bike adapter, but I think we can do better and have it included in paper form as well, so you have it with you in the workshop/garage as you are installing. We will get on this asap.
True - with the wider stirrups, the little one's riding position adjusts a bit. I am sorry your kiddo's not as comfy with the adapter installed. Fingers crossed as they grow, this will be less of an issue and you guys will have many happy happy memories on your Mac Ride! Best, Ashley