[BRENT in 10-uh-C]

The biggest issue with Brookville's open-cab pickup bodies is you still have the ingress/egress difficulties because the door stays the same width.

If someone is looking to fabricate a longer cabin, in my opinion they would be better to use a 30/31 Tudor as the foundation and shorten that. Then from the belt moulding down, use 82B body rear cross-sill and sheetmetal patch panel materials to remake the lower half under the ¼ and rear windows.

Then to keep the shortened bed from looking too bizarre, fabricate a 66A DeLuxe Pickup Bed like used on Service Bed vehicles that attaches to the body (see attached pictures).
.
.