The block should have the two threaded bosses in the lifter valley. If so you can use the factory roller lifters,dog bones and retainer to convert to roller. You will need the shorter roller cam push rods as well.
But, the distributor gears are different. Flat tappet cams are cast and use a cast gear on the distibutor.Roller cams are steel and use a steel gear...you CAN NOT mix match them or you will eat the softer gear away to nothing sending metal shavings through your motor.