The actions of two men who sent parcel bombs to Celtic manager Neil Lennon and other prominent figures connected to the football club were jailed for five years.
McKenzie, from Saltcoats, Ayrshire, was also sentenced to 18 months for a separate charge of posting a hoax bomb to Lennon at
Muirhead, from Kilwinning, also Ayrshire, was cleared of the charge with a not proven verdict.
Both men were originally accused of a more serious charge of conspiring to murder their targets but it was thrown out a day before the trial concluded due to insufficient evidence.
He said: "It is incomprehensible that two such family men, in their 40s, would engage in such reckless and serious criminal conduct.
"Even the sending of a package as a bomb hoax would always be a serious offence and would be bound to result in a custodial sentence - that is because of the widespread disruption and anxiety caused by such conduct."
The judge said it was "obvious" he was not dealing with what would be considered "acts of terrorism".
The jury heard that McKenzie told police he learned how to make a hoax bomb after seeing it on the 1980s TV show The A-Team.
Giving evidence at the trial, Lennon said he was left "very disturbed" after finding out he had been targeted. He said he "couldn't believe the lengths some people will go to".
The plot centred on four suspicious packages, all of them non-viable, discovered last spring.
A device sent to Lennon at Celtic's training ground in Lennoxtown, East Dunbartonshire, was intercepted at a sorting office in Kirkintilloch on
It tested positive for peroxide, which can be used to make explosives.
Two days later a package delivered to Ms Godman's constituency office in Bridge of Weir, Renfrewshire, caused the evacuation of the building.
Liquid inside a plastic bottle within the package tested positive for a small amount of the primary explosive triacetone triperoxide (TATP).
Before the incident, Ms Godman, who was Labour MSP for West Renfrewshire, had been filmed wearing a Celtic strip to the Scottish Parliament, which she claimed was meant to be a private matter.
After two failed attempts, it was sent to the Royal Mail's National Returns Centre in
The final package, found on
The lawyer, who died suddenly days before he was due to give evidence at the trial, was known to have represented Lennon and Celtic.
The prosecution's case was that even though none of the devices were viable, Muirhead and McKenzie believed they were capable of exploding.
Defence QCs Gordon Jackson, representing Muirhead, and
Lord Turnbull said today: "There was quite simply no relevant sense that it could be said that any explosive material was present. There was also no form of detonator or method of causing ignition."
"There was no risk of injury to anyone beyond the risk of some accidental contact with nails present in the various packages - and these aspects are taken into account in deciding the appropriate sentence."
McKenzie blew a kiss to his family as he was led away from the dock while Muirhead looked at the floor and shook his head.
Both of their sentences will be backdated to
When they were convicted last month following a five-week trial at the
Lennon said he was glad the "stressful and difficult" ordeal was over, but he wished his good friend Mr McBride had lived to see the matter brought to an end.