I would like to see a breakout for the Model D and Neutron that restores the rear panel connections that are lost when removing these units from their case to install in eurorack.
Which you shouldn't do. Not only do you run into the issue you've mentioned, you're also making the device you're UNcasing and REhousing more expensive than it already is!
An illustration: let's say you want to put a Moog Mother-32 into your snarzy new Pittsburgh EP-208. Sounds sensible enough...but then, let's do some math here.
A Mother-32 takes up 60 hp, and streets for $649. It has its own case and power.
The Pitt cab streets for $699 and has 208 hp total. 699 / 208 = 3.36, which is the per-hp cost of the cab.
So you stick the M32 in there. All of a sudden, here's what happens once you tighten down the last screw...
3.36 x 60 = 201.60. This is what it costs to do what you just did, which makes the M32's ACTUAL price in this situation $850.60!
Did you pay that much for it originally? No? OK...then why pay that NOW?
Eurorack cases are really for devices that DON'T have a case and power. Those devices require it. The Mother-32 in this example...no, it doesn't require it since it comes ready to rock out of the box. Yeah, I know, you see a lot of people on YouTube and the Interwebz in general doing this...but they're actually QUITE wrong in doing it. And I understand the whole thing about "convenience" and all that...but that "convenience" costs in exactly this hidden way. In short, I quote Admiral Akbar: "IT'S A TRAP!" Don't fall for it.