Naismith leads Rangers rout
It was the ideal way for the Scottish champions to erase memories of that League Cup exit to First Division Falkirk and ensure McCoist was able to enjoy his 49th birthday.
Rangers were on top from the start. Gregg Wylde sent a swerving free-kick into the penalty area and was only denied the opener by a good save from goalkeeper Paul Gallacher.
But Gallacher was left picking the ball out of the back of the net with just eight minutes gone when Rangers took the lead from the resultant corner. Steven Davis picked out Bocanegra, who connected well to nod past Gallacher and claim his first league goal for the club.
Rangers doubled their advantage after 17 minutes when Edu collected a short pass from Nikica Jelavic and sent an impressive strike past Gallacher from 20 yards.
McCoist's men could have added to their lead when Jelavic set up Davis but his poor header fell wide of the target, before Wylde tested Gallacher with an effort that the goalkeeper initially spilled before recovering to smother.
Naismith strikes twice
Dunfermline's hopes of a comeback in the second half were dealt a blow when Rangers found the back of the net again just six minutes after the restart.
Naismith raced onto a pass from Davis and kept his cool to stroke past Gallacher from 12 yards, before Steven Whittaker went within inches of adding his name to the scoresheet with a well-struck shot from long distance that dipped but went just over the crossbar.
It was proving to be a busy afternoon for Gallacher, who was called into action to force a Jelavic free-kick over, before denying a ferocious effort from Whittaker. But he was unable to prevent Naismith from claiming his second of the day with nine minutes remaining.
Davis went on a great run before finding Jelavic, who whipped the ball across the face of goal for Naismith to rifle home from close range.