I've never assembled that particular control panel. I don't know if it will help but here's what I've found useful while building my own control panels (I have a similar one for a RIMs setup & I'm piecing together a larger system). I'm also not an electrician or anything.
For a lot of stuff it looks like The Electric Brewery
might help you out. There are some pretty detailed instructions on there. Particularly you might want to start with: Control Panel (Part 1) - Step 4: Cut Holes
I think I actually used a 1/2" conduit punch (7/8" holes) to make holes for my 22mm components instead of the step bit mentioned.
Looks like your enclosure already has the hole for the PID - which is nice because I think that's probably the worst hole to try to make. The rest of the external stuff should basically be punching holes of various sizes & attaching components.
Seems like you want 3x 22mm holes in the front for those push button switches, a couple smallish holes in the side for the temp probe wire & the power-in wire, & two holes in the back for pump-out and element-out sockets.
As for mounting other components internally - I've found that using crimp connectors help for connecting wires to different components. Most of the pieces I've used I could bolt onto my enclosure... so more little holes for bolt + nut.
I realize that's probably not as helpful as you'd want but maybe it's enough to get you started (or someone else can provide better info for this particular build). Just remember - measure twice (or three or four times!) & cut once