As above, bigger yoke and also heavier duty axles and bearing retainer rings. You can buy an adapter uni with the 1" V8 cups on one axis and the 1.125" tonner/350/TH400 cups on the other axis.
You'll most likely find tonners in 3.55:1 or 4.44:1. Some had 3.36:1 but these were only ever on V8 autos and very scarce, normally only on 308 TH400 although I have recorded a 253 trimatic with one.
Bookmarks