The RCO -0,1 or 2 are equal to the CFNO, CFN1, CFN2 and maybe the DFN0, DFN1, DFN2 prompts. You print then in
LD 21
REQ: PRT
TYPE: RDR
To chg these prompts - use LD 15
REQ: CHG
TYPE: RDR
<cr> until you see the prompt you want to change and enter the new value then <cr> until you get the REQ prompt again.