The frame and the PiZero are a perfect match for each other. The fit is tight but there is just clearance to fit the PiZero and the PCB between the top and bottom plates, but because it’s tight, there are a couple of things to be aware of.
First, the velcro attaching the LiPo must be 20mm wide or less. Before sticking the PiZero to the bottom plate, attach your LiPo to the underside with the velcro. That then defines the length of double sided sticky foam tape between the velcro straps that the RPi is stuck to on the topside of the bottom plate. Done like this, the two ends of the PiZero overlap the velcro, but the 40 pin connector does not.
Because the PiZero ends overlap the LiPo velcro, the underside of the PiZero needs to be flat at the ends; the mounting holes need to be countersunk from the underside and M2.5 countersunk bolts are used.
I’ve used some very thin non-branded velcro and that means I’ve used only 1mm foam tape to stick the PiZero down. I have no idea where I got the thin hook-and-loop tape from, it was acquired sometime in the last 3 years of the project. If you use thicker velcro, you’ll need thicker double-sided foam tape and that might breach the height limit between the top and bottom plates – yes it really is that tight. But there is a solution.
The 90° pins the ESC cables attach to are high profile; this was necessary for Phoebe and Chloe as the PCBs had wires on them; the pins needed to be raised over the wires. Zoe’s PCB has no wires, so standard low-profile pins can be used. This will buy you the couple of millimetres you need to use the thicker double sized tape to stick the PiZero down.
One final comment: the velcro tying the 5V battery bank to the top plate also needs to be less than 20cm wide. That way, it passes over the MPU-9250 but between the ESC cable pins; any wider and it and the ESC cable pins will overlap and you won’t be able to plug the ESC wires in.