Tuning Seletron Chip Box

[Tramonto]

I have a 2015 Fiat 500L automatic with the 1.4 160hp. I got the Seletron Chip Box. There are 3 locations that are to be hooked up and to me the instructions are not very clear on this matte. The 3 locations are called PREX1, PREX2, PIERBURG. I have a general idea where they are but not definitely. Does anyone know where these are? I have I.D. three wires but I am not sure. Thanks in advanc.