Sometimes "Open 24 hours" has its disadvantages-like when two diminutive mavericks decided last week to use a convenience store of the same name as an early morning cash machine. Police are still on the lookout for the two Hispanic men, one described as five foot, nine inches and in his 40s, the other five foot seven and in his late 20s, who knocked over the Maverick at Cloverdale and Ustick at 4:36 a.m. on June 16. The pair were in their finest soldier-of-fortune duds, one donning a camo jacket and the other an all-black pant-jacket-cap ensemble. They entered the store, claimed to have weapons, made a few demands and evanesced into the damp embrace of a late-spring morn with an undisclosed amount of scratch. What a way to start the day.