Im in the process of this as well but i have a head start as i have mostly populated playfield to start.
I built a few cabs years back that i have sold but i have my test cab that i first built and will be using that, its good but was just made with some unfinished plywood in certain places.
I will be building my own wire harnessses(all except playfield), light boards, speaker panels so if you plan on doing this and need something let me know.
I do plan on building a few more cabs in near future but probably just cheaper for you to go through virtual pins.