Simplify the following text for a Grade 7 native English-speaking person.
Original: Formed by the Abbott brothers , Vinnie Paul ( drums ) and Dimebag Darrell ( guitar ) in 1981 , bassist Rex Brown would join in late 1981 with vocalist Terry Glaze .
Simplified: They formed in 1981 , but they did not have success until the late 1980s . From 1987 to 2003 the band had these members : Phil Anselmo ( vocals ) , `` Dimebag Darrell '' Abbott ( guitar ) , Vinnie Paul Abbott ( drums ) , Rex Brown ( bass ) .