Forward March
by Kegler

Some answers, clued normally, are one letter too short for the grid; the blank square may appear anywhere in the entry.   The remaining clues each contain an extra
word, the first letters of which in clue order describe what goes in those blank squares (the results will be new words or proper nouns).  One answer is an acronym.

Across 1 Television performer playing sitar ahead of time 6 A Hessian soldier gets into trouble slowly 11 Noble ape enjoys cavorting with skinny person 12 Kook’s large cask overturned 13 Favor bishop to a smaller extent 15 Liberal governor turning South American city purple 17 Radio intelligence operators describing itinerant son’s carriages 18 Band recalled sign of boredom about retail store ultimately having a no-return policy? (hyph) 19 Composer’s lyrical debut with self-adjusting musical symbols 23 Professor’s audibly exhaled team spirit 24 Rouse prison officer 26 Need new flower garden 28 Mother with cold Bud 30 Lonely individual following doctor’s monotonous talk 31 Policeman has nearly completed work with ink pen (2 wds) 33 TVA supports keeping pair of veteran dam-builders 36 Sue temporarily storing it in hotel rooms 37 Laughter and endless glee after band’s last performance 38 Measure existing breathing apparatus 39 Wooden shoes are wrong for beach 40 Uses powerful beams and basks in the sun, we hear 41 More than one observer saw drunk cat backtracking

Down 1 Sea creatures with massive isolated stomach muscles on the outside 2 Reportedly poured under control 3 Story about bachelor’s excessive delay 4 Foreign swain accepting fifty nice wedding acquisitions? (hyph) 5 Nonsense being shot out 6 Young Albert’s #1 region in France 7 Leading study about a big man on campus? 8 Australian oak is essentially covering flowering plants 9 Emits undeniably strange things 10 Locals oddly ignored association of western countries 14 Italian noble frequently seen within borders of Lombardy 16 California nurse circles one sandstone rock monument 20 Cools off annoying crazies 21 Rejected, heartlessly take part in mangling circus equipment 22 Wild armrests flare out 25 Unusual yoga routine not yet delivered? (2 wds) 27 Carol’s collecting five adventure books 28 Sitting in Hummer limousine, gestures and pulls into traffic 29 After Saturday, desired nothing 30 Satan was called up 32 One left in pot for opponent’s ace, perhaps 33 Impressive bartenders invariably get tips 34 Discarding the first rental agreement for tech facility 35 Mr. Walton takes on one trainee in Anna’s workplace?

Solution