Mitsuko is a pretty standard build, except smaller. Here's a couple of tips, using a FrSky X4r, RMRC Dodo, T Motor F40's, and Kiss 18's on a 5" X frame. The same principles apply to the 4" +, except you have to be even more careful with keeping the wiring tight and away from the props.

Glue the camera first, maybe it'll be set when you're ready for it. The flat edge of the plate is the top. Fun fact: Alex Walsh would marry FoamTac if the law allowed it. (It does a better job than hot glue here.)

You have to de-pin the rx to make it fit (more important for the 4" plus configuration). Cut the plastic retainer so that each pin is on its own, clamp the pin, heat and pull the rx off. (Or you can buy this naked X4R from Rotorgeeks.)

Signal, pos, and ground leads soldered.

I use X-Treme tape instead of heat shrink. It's a silicone tape with no adhesive and it only bonds to itself, I think of it as heatshrink you don't have to plan ahead for. It's a little thicker and has some give – stuff is going to get squished together so a little padding is nice.

Leads soldered to Dodo. Sbus signal goes to port 3. I really like how simple it is to use sbus with the Dodo, just go to the Ports tab in Cleanflight and choose Serial RX for UART3, followed by the Configuration tab. Choose RX_Serial in the Receiver Mode box, and Sbus in the Serial Receiver Provider box.

It's going to get squeezed together like this. A cool feature of the Dodo is that usb will power the rx, so you can bind it with your tx now. 

This Abusemark pdb is two-sided. Make sure the pads align with the esc pads. There's a nut under the pdb to leave room for the strap.

First one wired up, note how the leads arc around to leave room for the nylon standoff. Double stick tape under the esc.

All four motors, power to Dodo, and vtx power connected. We're done with this layer now. One of the coolest features of the Dodo is its ability to take direct battery voltage, which really simplifies things here.

The Dodo goes on, sandwiching the rx, signal wires connected. Normally I'd push the leads through the holes before soldering, but since things are going to get smushed I soldered them laying flat. 

Test fit of the vtx. Be careful with that push button, it's easily knocked off (the vtx will still work without it). That little rubber o-ring is a tip from Josh. It does a great job of holding the vtx on, doesn't use up a whole lot of threads, and provides some friction for the antenna nut. The esc's are wrapped in X-Treme tape, after getting motor rotation sorted. X-Treme tape is really nice for tight builds, no need to work around heat shrink, just wrap it up when you're all done, and with the clear tape you can see your esc led's.

Here's the pod built up (I mistakenly picked the wrong lens, it'll be swapped out). Use loctite on those retaining nuts, and just moderate torque. Too much and you'll crush the carbon. Note that the curved side of the cam plate points down. The plate holds better with the hooks pointing down.

Attach the pod and you're done! 305 grams without battery. Lighter 2204's would save a few more grams. She's a rocket!