I have a set of st185 front disc brakes from the engine swap i did to my 96 gt. Are these brakes interchangeable with my car and would they be an upgrade?

depends what ones you have as the early ST185 (my 1st gt4) came with ST165 set up and the discs are about 20mm smaller, do you have the single piston or twin piston caliper? i've had both with my ST185 ATA and my Carlos Sainz, could you not get your hands on a ST205 for the parts shipped in for the exchange.