Here is a GTL example from a colleague that demonstrates how to create a "splitchar" axis. The keys here are splitting the text in the datastep, turning off the axis tick values, and using a blockplot to render the text.
length line $20;
input Answer Question $3-70;
do while( lengthn(line) > 0 );
3 #1~How do you~feel today?
4 #2~Would you be~willing to try this~again?
2 #3~Is there some~way to get there~from here?
5 #4~When do you~think this will~be finished,~today?