Very nice and congrats. I like my HRDX too, but I like the look of yours better. Mine is black. I was going to mention the 5881s too. I put them in mine and haven't looked back. It's been so long since I had the 6L6s in it that I forgot what it sounded like and almost made a swap, but then I'll play it for a bit and go, "nah sounds good as it is."
I've never really had a problem controlling the volume on mine, but I have seen a lot of guys use a Hot Plate with good results.