The OEM side door well is pretty generous though. Wondering how I can retain this whilst also adding a couple of other slots like you've done,.

Got them off eBay for about £20 the pair. They are 5Ltr containers. If you use that in a search on there these should come up from various sellers.
I’m looking into doing exactly this as well. Except doing the work myself to hopefully save money, and perhaps learn for the next build.PJD wrote: ↑Sun Apr 07, 2024 9:43 pm Yes both sides. The other is a slider.
For me fitting the windows became a bottleneck to continuing the interior and I couldn't foresee a dry day anytime soon. Sounds like you are in the same situation. Carpeting seemed pointless if I was going to create lots of metal dust later so was holding off making progress.
When I got my van MOTed I dropped by a nearby campervan converter on the same unit and the price and convenience sold me.
Would have loved the satisfaction of doing it myself but won't be my last van conversation.