As it was coilpack to start with, you just need to add another two wires to each side of the coil circuit, so 1 feed becomes 2 feeds.
On the std coilpack centre is Live, this will need to go to all 4 coils, then the left terminal will be the negative(ecu switched) feed to cylinders either 1 and 4, or 2 and 3, so take this to the relevant new coils.
tabetha