The Matchbox MoYY 1912 T Model Ford trucks are listed at 1/35 so yes, too big. Interestingly their 1911 T Model Ford car shows 1/42, still too big for MY eye to accept.
Personally I find the Lledo Fords of all eras & ilks a better fit for 28mm than Matchbox.
Remember these are "Box Scale" toys, meaning the smaller the actual vehicle the large physical scale they make it in, & vice versa, so it fills the display carton, & sells!!!
T Model Fords & the Later A models as well, aren't very big by modern standards, stop by a classic car meet & see for yourself. There you'll find diminutive sedans and monstrous two-seater touring cars along with commercial vehicles you wonder how they ever carried enough to pay for themselves!!
On the gaming table use the Mark I eyeball gauge, if it looks good with your figures, then how can it not be right? My "sweet spot" is in the 1/50 - 1/54 range for my based 28mm+ Pulp People. Others like 1/43, which I find visually too big, thus making them WRONG...
1/35 is actually Tamiya tank scale, & will dwarf most 28mms, stay far away lest whispering, pointing, giggling & teehee-ing or tisk-tisk-ing occur.
VMMV
Valerik
Mk I Eyeball, works better these days, but range is, er, um, uh, problematic at times...
EDIT: my miserable spelling
