2013 Mazda BT-50 Gsx D/C W/S

2013 Mazda BT-50 GSX Double Cab This has been a builder's work ute, unfortunately it has a blown head gasket. The body and interior is in good condition for its age BELOW IS THE REPORT FROM THE MECHANIC Customer - T control light came on. Then at an intersection, taking off, blew lots of white smoke for a short time. Temp guage wasnt reading, then it was - Then went high turned the vehicle off & on then it went back to normal temp. Put 3L of water in over flow bottle. Bubbles starting coming into the over flow tank. -Scan for DTC's. Long road test. Coolant down alot after test.Tested for gases in coolant, going up and down. Lots of grey/white smoke on idle. Check EGR for coolant - now - ok. Check Cylinders on scan tool - #3 & 5 are average. Head gasket blown.