He was jailed in May for nine years and six months, with a non parole period of four years and nine months.
Shelford is in custody awaiting sentence next month.
The violent attack was sparked when Lemon's special needs brother was intoxicated and stood at the front of the property on William Jones Dr, yelling abuse at passing vehicles.
Sentencing Frederick Samuels, Judge Keith de Ridder said his brother who was driving past stopped his vehicle, got out and became involved in a verbal altercation.
Frederick Samuels left but returned with his brother and mother a short time later in three separate vehicles.
Judge de Ridder said Lemon came out, apologised to the brothers, and urged them to leave.
He said Frederick handed a piece of timber to his brother who swore at and threatened Lemon.
As Lemon momentarily turned to speak to a family member, Tangaroa Samuels swung the timber baseball style across the back of Lemon's head.
Lemon dropped to the ground, struck his head on the concrete driveway and began to convulse.
He was rushed to Whangārei Hospital in a serious condition but was soon flown to Auckland where he had surgery to alleviate the bleeding and pressure on his brain.
Judge de Ridder said Lemon suffered a perforated eye and multiple fractures at the back of his head.
Doctors told his family not to expect him to survive, he said.
He accepted Frederick Samuels had a somewhat lesser role but only to the extent he didn't swing the piece of timber.
"In my view there's a very limited distinction because you went to the back of the car and the two of you uplifted the timber before going to the family's home."
Lemon needs help with aspects of his daily life such as going to the toilet and interacting with his grandchildren.
