I'm slightly confused by the designation of R4 for the bottom row containing the spacebar. AFAIK, there are no R4 spacebars or 1.25u mod keys. I think the diagram should refer to them as R3. The Signature Plastics spec sheet calls them R3, and to the best of my knowledge, they have the flat (0-degree) profile of row 3 keys.
If I am wrong about this, please educate me as this would constitute an interesting new development for SP's SA-family keycaps (not as ground-shaking as proper R4 shift keys, but still...).
JohnRCooperIndeed spacebars are row 3. Displaying it right i need to break the layout, so i kept it there. You are right i had to notify it like i did with the shift keys.
The 1.25u keys are available in row 4. I guess your SA family listing is not up to date.
If you like, you can ask SP for an up to date SA Family listing. Though you can find on SP page already SA Family listing but AFAIK its outdated.
If I am wrong about this, please educate me as this would constitute an interesting new development for SP's SA-family keycaps (not as ground-shaking as proper R4 shift keys, but still...).