rear brakes on tuscan road/trackday converstion

[993phill]

as it seems i have a knackered pair of 2 pot rear calipers does anyone know if i can fit the griffith calipers in there place thus giving me a mechanical handbrake at the same time {i know this has been done}
if so any ideas what i need to do/get to achieve this
or failing that any other ideas willwood for eg

many thanks