I think the premise of the letter is "we saw you purchased from diversified machine. We searched our databases and dont see you listed as having registered any nfa items"
A buddy bought from diversified machine, he did the proper form 1 stuff, got approved and all that. I asked him about his kit, and he said the "kit" is pretty much all finished with the exception of the end cap not being drilled.
C'mon, that's poking the bear, that's along the lines of those 80's that were all but done with the FCG filled with some polymer you could scrape out.
Its not surprising to me anyway. Other solvent trap kits i've bought had to be finished 100%. I did my form1, got approved, went and had it engraved, THEN built it. Some companies you have to provide them a copy of a submitted form1 before they'll sell to you.
Theres good companies and products out there for the DIY'er, then there's companies that just wanna flirt with authorities.
I'm not supporting the ABC's here, just stating what is obvious, not that I agree with it.