Hello i d like to fix ate first series calipers (distance between fixing holes 3 inch) instead of girling or 2000gtv calipers on my giulietta sprint veloce, converted to front Disc brakes.

Does anyone sell or can make the adapters like in picture, modified with 3 inch distance between caliper supporto holes? Will in this case they work?
PS i have original girling kit and adapters, i m also open to modify them if It can be fine.
Or, can i make them with 3d printer and if yes which materiale?)
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