Years ago when building custom vans, we used to attach extenders to the crank window crank posts for the handles to work with all of the plywood and shag carpeting. Where can I find door handle extenders today? I made new custom door panels for my car and the window handles won’t fit anymore.
Your problem is not unique to custom vans, I have known many hot rodders that build awesome tuck-and-roll leather wrapped door panels and encounter the same problem. There is a company named “Resto-Mod of Connecticut” that manufactures these. Their store is run through eBay and you can order or contact them through the site. They also offer custom services to make extensions to fit your exact application too.
Do an eBay search for: Window Crank Extension