Converted mine to side hinged and insulated with 2" EPS, then 'added' a side door, and never looked back.
Took a week of figuring out and helped by neighbour on the day.
I was lucky as there is a Carport in front, so protected from the elements.
Details here but the Album I referred to has either gone AWOL or I forgot to add it.
I did the same on the Carport extension, converting the bare bones 'Up and Over' to hinged as well, but there was space for a standard door on the side.
Had to wait nearly a month for the right conditions of no rain and wind to get it bolted up, as it acted just like a flipping sail in the slightest breeze.
Geoff – I just happen to live in the windiest part of town.