Put in this fine little BASIC program and off you go !

5 input "enter current and new sd2iec number";a, b
10 open 15,a,15,"u0>"+chr$(b):close15
20 print "sd2iec new device number is:";b
30 input "permanent change? y/n";c$
40 if c$<>"y" then goto 70
50 open 15,b,15,"xw":close15
60 print "permanent change done"
70 input "reset sd2iec ? y/n";c$
80 if c$<>"y"then end
90 open 15,b,15,"u"+chr$(202):close15
100 print "reset done !"