I built that bench, completing it last December (thus, it must have been 12/03 edition of FWW, not 12/04, or I'm thinking of a different bench). Of course "built that bench" is a little bit of a lie, cause much like recipes, plans are more guidelines to me than something to follow religiously.
I built the trestle nearly identically, except I made the stretchers longer (because the top is longer...) I think my stretchers are 54" between trestles vice 51" in the plans. I believe the plans have the trestles of all the same x-sect (3x3) except the base which 3.5 high to accommodate the cutout. My legs were 2.75x2.75 to create a reveal. pegged & wedged like the drawings though.
The height will depend on you & thickness of slab. I like a taller bench even though I'm short (5'8"), and I matched to my TS. The bench is 35.25" in my case at the top of the slab. My slab was 2.75" thick, about same as the article. What I did was ripped 8/4x6 hard maple in half and used the max thickness I could manage, ending up with a 2.75" slab. The aprons on mine are 7" wide, cut from 8/4 x 8 stock. The endcaps are doubled-up 8/4, as are the vice faces. Those are heavy pieces of wood. I didn't put an apron on the backside because I wanted to be able to reach under the top if something fell through and landed on the cabinet (yet to be built). If you run the apron all around you need gumby arms to get in between the upper stretchers, with a cabinet.
His bench was quite wide 27-30" IIRC. Mine is 24" because I have a narrow (13' shop) with a lathe and jointer in the area that make it even narrower. I made it 78" long, which was a little longer IIRC. Round dog holes not square 'cause I like the the LV stuff for benches. And they're easier. I put holes along the front apron and in the side of the end vice - allows a "bench-slave" like arrangement. I also mounted the front vice differently, following an idea from the 12/02 FWW to bury a regular quick action "record" vice (which I had) into the back of the apron so the apron is a continuous run - looks & works great. I also think that design had a tool tray, a feature I abhore as a space eating (damn narrow shop again) and worse, tool, dust and junk collection tray. But people who are more disciplined probably love them.
At any rate, I finally requested SWMBOs help, needed to flip the top over as the last step. And at nearly 7' long with the end vise, 2' wide, as thick as the top and aprons are, with two vices hanging on, that sucker was heavy. She looks at the bench after helping and complains that it is the nicest-looking piece of furniture in the house
- and - it's a damn toolbench. Knows how to make me feel good ;-) As a relative newbie, it is my finest quality work. Although to the average joe my son's loft bed (which has a gorgeous curly maple veneer, cut by me out of a piece of $1.60 per bf pile of soft maple I bought, on the visible stretcher) looks better and has fancier joinery. Far fewer mistakes on the toolbench though. And it took me only about 4 weekends to build versus almost 4 years for the bed.
So if you're still reading after this incredibly long-winded non-answer to your question about "what are the friggin dimensions," my point is that I think a workbench is such a personal piece of furniture you want to fit it to you (and your shop), and not to some plans for some other guy. Take the good ideas (the base is really well designed imo, and worth copying) and combine other ideas (like using an existing vice an another workbench design) and end up with your bench.
Have fun