Kieran McGrath, 26, was shot after leaving the Sheldon Arms pub in Ashton-under-Lyne on 4 October 2014. He drove to a police station but died later.
The man who orchestrated his killing, Anthony Henry, 32, was found guilty of murder on Friday.
Troy Beckford, 24, and Jace Smith, 31, were convicted after a trial at Liverpool Crown Court.
The jury was unable to agree in the case of two other men, Remi Adams, 34 and Scott Chapman, 27, also charged with murder.
Mr Adams was found not guilty of possessing ammunition without a certificate.
A woman, Bretony Gallimore, 24, was found guilty of assisting an offender.
The gun used to kill Mr McGrath was the same gun used to kill Manchester shopkeeper Pragaret Singh three weeks later. Police believe the firearm was passed between criminals.
Mr McGrath was shot after leaving the pub at about 22:25 BST.
Anthony Henry had tracked Mr McGrath's Audi S3 and watched his movements on an iPad, the trial heard.
After being shot, the 26-year-old drove away from the scene to a nearby police station but died after collapsing near the front door.
He died from a single gunshot wound, a post-mortem examination found.
No witnesses to the attack have come forward.

The Latics lost 1-0 at home to fellow relegation candidates Bristol City on Saturday to leave them four points from safety with nine games remaining.
Former Manchester United Under-21 manager Joyce, 52, took over in November after Gary Caldwell's sacking but only won six of 24 games in charge.
Assistant manager Graham Barrow will take charge for the rest of the season.
"It is unfortunate that we have made this decision but with the team in such a perilous position in the league, we need to act now because we cannot afford to fall any further behind," said chairman David Sharpe.
"Results and performances have simply not been up to standard often enough in recent matches.
"Although we acknowledge the difficulties faced in managing a team in a league where we are competing against clubs with much larger budgets, the nature of some of our recent defeats, especially against close rivals, has fallen short in terms of what we as a club, and all our supporters, expect."
Former Bolton, Preston, Plymouth, Burnley and Hull City midfielder Joyce signed a three-and-a-half-year contract with Wigan, but has left along with first team coach Andy Welsh.
After winning the League One title last season, the Latics have struggled in the second tier, and are the lowest scorers, having failed to find the net in 10 of their last 14 home matches.
Barrow, 62, is a former Wigan midfielder and manager who returned to the club in 2009 to work as a coach under Roberto Martinez.
Two more men have been found guilty of murdering another man who was shot outside a Greater Manchester pub.
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Championship strugglers Wigan Athletic have parted company with boss Warren Joyce after only four months.