rewrote it into 31 bytes

( 76543210 fedcba98 -- _____0__ _fe76dcb a9854321 ) OVR STH2 ( 76543210 | fedcba98 76543210 ) #01 AND #20 SFT ( _____0__ | fedcba98 76543210 ) STH2kr #01 SFT2 #601f AND2 ( _fe_____ ___54321 | fedcba98 76543210 ) STHr [ LIT2 00 be ] SFT2 ( ___76___ ________ | fedcba98 ) STHr #3f AND [ LIT2 00 03 ] SFT2 ( _____dcb a98_____ ) ( _____0__ _fe_____ ___54321 ___76___ ________ _____dcb a98_____ ) ORA2 ( ___76___ ________ _____dcb a98_____ -- ___76dcb a98_____ ) ORA2 ( _____0__ _fe_____ ___54321 ___76dcb a98_____ -- _____0__ _fe76dcb a9854321 )

… welp, still too slow

#01 #20 #01 #601f #3f #01 #20 #01 #601f #3f