Rear disk brakes To do or not to do?

Car was (69 cuda fastback) four corner drums, fronts have been converted to disc , rear is stock and shoes are done from burnouts, I did replace all 2 yrs ago but everything is shot, I have replaced the peg legger for a 489 3:55 s/g axles are drilled to lbp w/green bearings my thought were to replace brk component again and drill out drums to fit,........or just go to rear disc. The feedback is great and I do like upgrades ......still on the fence!!!