For reasons that remain unclear, McQuillan failed to negotiate a bend in the road and crossed the centre line, moving entirely into the northbound lane, colliding head-on with Searle's truck.
Searle had no chance to avoid the crash and lost control of the truck, which crashed through a roadside safety barrier, down a bank before coming to rest on the bank.
The truck then caught fire and Searle suffered multiple injuries, including burns, and died at the scene.
McQuillan suffered head and abdomen injuries and taken to Waikato Hospital by air ambulance.
A blood sample - taken seven hours later - revealed 0.43mlg of P in his blood.
Police then found three large 2 litre Sistema containers in his car with what appeared to be remnants of a large amount of white crystal material and a small snaplock bag containing 0.9 grams of P.
A snaplock bag with 1.5g of MDMA was also found, along with 49 rounds of 20-gauge ammunition and a .308 round.
At his Omanawa house, police found 93 rounds of shotgun ammunition and a .22 along with various drug utensils.
In the Hamilton District Court this morning, McQuillan also admitted possessing methamphetamine and MDMA and a representative charge of ammunition and explosives.
He was convicted by Judge Philip Crayton and remanded on further bail for sentencing in July.
