This is a bit of a cheat since I don't actually own this radio. I had bid on it on an auction site and researched it. I had thought I'd win it but eventually outbid, which surprised me. I'm not a big fan of the cabinet style and I don't think they're valuable. On the other hand, they were popular at one time; I see these for sale all over the place.
But as I said, I'd researched it so I know something about it, which appears to put me ahead of a lot of people on the net who are selling these things, so here we go.
The X334 is a table-model AM/FM tube-radio named "The Highlighter." (Zenith tended to name their radios.) It was manufactured in 1967, and it appears in sales literature from that time. That's also the year the SAMS Photofact was made for this chassis. A lot of people date it from the 1950s (or earlier) based on the patent dates cited on the label. Uh-uh. If you were around in the late 60s/early 70s, you recognize this style. It looks like several television cabinets I grew up with.
There are two styles of cabinet, and the last letter of the model tells you which: the X334M is American Provincial and the X334W is Danish Modern. Once you know what to look for it's easy to tell them apart, but they're largely the same. First, there's the grill cloth. The American Provincial has a tighter, patterned weave; the Danish Modern has a heavy block pattern.
People complain that it's difficult find a schematic for it—that's not true; it's difficult to find a free schematic for it. SAMS Photofact Set 916 Folder 8 covers it. The problem is that SAMS wants $22 for it, so you either have to pay up or ask someone for it (don't ask me—I don't have it).
SAMS, however, has (or had) a reputation for mistakes. You can find a "corrected" Zenith X334 schematic here that's free.
It appears that there are two chassis versions inside this unit, the 7N05 and the 7N07. The difference between them appears to be slight: the 07 has a dial lamp and a couple more bypass capacitors in the output stage. I have no idea whether they sold both chassis concurrently, one as a "deluxe" model and the other the base, or if they added the dial lamp and caps to improve the model, or deleted them as a cost-cutting measure (I tend to believe the last).