Obviously I can’t rely on my old floorboards as a guide for putting together my new floorboards.
I have rivets where there shouldn’t be rivets, and the other fasteners are an assortment of what appear to be “field (garage?) expedient.”
Since I’d like to put her back together as close to original as I can, I’ve got questions.
The directions that came with the floorboards tell me to use #10x5/8" wood screws for the three brackets that join together the #3 floorboard. I assume these would have been slotted, but the local ACE didn’t have any. They did have Phillips heads so that’s what I got for the meantime. The problem is the heads are too large and don’t fit flush into the steel brackets so they look pretty rough even though they’ll be out of sight underneath the car. Is that considered acceptable? If not, what kind of screws are your #3 floorboard brackets attached with?
Thanks!
I just heard from a friend who inherited several boxes of NOS period wood screws, so I’m making some time to explore his garage and check it out.
We’ll see 
Well, my friend brought over a box of NOS #10x5/8" round head slotted wood screws left over from another century. They look a lot better and take up no more of that precious clearance than those ill fitting flathead wood screws, so these are what I’m going to stick with until I can find duplicates for what Henry used, 
This was too easy of course. The pedal trim pieces are mild steel and I got them to fit pretty good. The long tabs need to be bent around the “fingers” of wood while the shorter tabs, I assumed, take care of horizontal play and are bent inward to not get in the way of the pedals.
In order not to mar the paint on the trim, I used a length of scrap Ash 1"x1" and a plastic mallet to tap in the bends.
Of course, one of the wood “fingers” broke 
Since the wood was loosely held in place by the bent metal tabs, I glued it back together with Titebond II
Clamping to get the glue to bond well didn’t work as the wood wouldn’t remain flat when I applied the clamp (FWIW I used a Pony pipe clamp) so I compressed the joint with one hand and with the other shot four staples spanning the break with a staple gun in order to hold the wood tightly together until the glue dries.
I’m planning to screw on a repair strap after the glue dries
So my question is, am I doing this repair correctly?
If not, how would you do it?
I repair things until they suit their intended purpose. Sounds like you got it right.
I think that shooting in some staples across the joint was some quick, intuitive and creative thinking. 