This is my home made 4x12. In 1980 I bought a Marshall amp, and it took all my cash to do it. I wanted a 4x12 so I borrowed a real Marshall 1960A and took it to a carpenter friend of mine, who cloned it precisely. I took it to another friend who covered it in protective fiberglas resin. I then put two Celestion GT-75s in the two top holes and played it for a while like that. After about a year I bought two Eminence speakers to fill out the bottom holes, and that's the way it's been ever since.
It was my only cabinet for 15 years until I built my 2x10 cab, and now I have other cabs as well. Eventually I sold the Marshall and switched to a stereo setup using two Fender Silverfaced Bassmans, and converted the cab to stereo. It doesn't sound exactly like a real 1960 cab, probably because it doesn't have Greenbacks in it, and the fiberglass resin probably affects the tone as well. All in all it's been a great cab. I hadn't played through it in awhile and recently when I modded my Bassman 100 into a tone monster, I put the two together and it sounded awesome. And yeah, it looks beat to hell, you would too if you'd been thrown in and out of car trunks and vans for 25 years.