A simple thing I could think of is:
Use When=Group, Records=2 and Push the entire first record (80 bytes) to 81 - 160. Then check if position 81 has a value but position 1 have a space; Overlay the space at position 1 with '*'. In the end Build only 1:80.
You'll have to check for all the possible 80 positions. So, the sort card gets repetitive and lengthy.
I am not sure if there is an easier way since the positions of blanks/asterisks on the second record are not fixed.