LAWRENCE – A Boston painter scheduled to go on trial Monday in Lawrence Superior Court for stabbing another man several times inside a Lynn bar in 2008 opted instead to plea bargain his case.Eduardo Ramos, 33, last known address of 33 Bacon St., Dorchester, changed his innocent plea to guilty to charges of armed assault with intent to murder and assault and battery with a dangerous weapon.Sentencing has been postponed until Oct. 13 in Salem Superior Court.In the meantime, Ramos remains free in lieu of $2,500 cash bail, but was warned by Judge Timothy Q. Feeley that if he fails to show for his sentencing the plea deal is off.He is expected to receive between 41/2 and 71/2 years in state prison.Ramos admitted he attacked 38-year-old Ricardo Ramos, of Lynn, (no relation) inside Molino’s Bar located at 937 Western Ave. on Dec. 28, 2008.Investigators learned that Ramos attacked the victim after they began arguing in the bathroom at around 9:30 p.m., after the victim mistakenly opened the stall bathroom door, which apparently angered Eduardo Ramos.As Ricardo Ramos exited the bathroom, Eduardo Ramos pulled out a knife and stabbed him three times in the chest area on the dance floor.Eduardo Ramos was quickly subdued by a bouncer and a worker inside the bar and held until police arrived.The knife was recovered by police at the scene.The victim was rushed to Massachusetts General Hospital in Boston for treatment and released after one day.The stabbing was captured on the video camera inside the bar.Assistant District Attorney John B. Brennan prosecuted the case and public defender Mark Schmidt was the defense lawyer in the case.