PhantomDingBat

I am planning to buy a Genesys ZU for some special image operations. I want to read and write images to RAM and SSDs in the host computer. PCIe 4.0 bus seems to be the best way to go because of bandwidth. There is a mini PCIe connector on the ZU. I would like to put the ZU in a box with a PCIe connector on a panel, run a cable from the ZU box's panel to the back panel of the host computer by using a PCIe card with a PCIe cable connector in the bracket. I am attaching a sketch (cabling diagram.jpg). About an hour of shopping has not produced satisfaction for a PCIe card (x16 or x32) with a mini PCIe connector in the bracket. Am I barking up the wrong tree? Can anyone offer a bit of advice?