Bloodstone: William L. McCaughey

Just for completeness, there is another variation of the name:

William Mc Caughey ==> The Goodbye Girl, The Chicken Chronicles.

Here is the end credit for "The Goodbye Girl" which show his credit (at 1:31 mark) as "William Mc Caughey, C.A.S.":
https://www.youtube.com/watch?v=E3P2mrblZVY&ab_channel=ImmortalityMovieMusicOriginalsoundtrack

In addition, there are five profiles for "The Goodbye Girl" in the online database, with four out of five profiles with "credited as" [William Mc Caughey]:

==> William McCaughey [William Mc Caughey]
5-051893-024180 (Spain)
012569-504820 (United States)
883929-155392 (United States)
888574-453145 (United States)

==> William McCaughey
FC30-8627-022A-0CFB (Canada)

'Don't Tell Her It's Me' (aka 'The Boyfriend School'): William McCaughey

'The Man Who Loved Women': William L. McCaughey

'Underground Aces': William McCaughey

William L. McCaughey sound department (sound re-recording mixer)

CLT results:
"William McCaughey" is credited in 72 titles (442 profiles)
"William L. McCaughey" is credited in 68 titles (293 profiles)
"Bill McCaughey" is credited in 14 titles (58 profiles)
"William Mc Caughey" is credited in 2 titles (5 profiles)
"William McCaughy" is credited in 1 titles (1 profiles)

William McCaughey (33 titles, 31 confirmed)
9 1/2 Weeks (confirmed by huskersports)
American Anthem
An Enemy of the People (confirmed by huskersports)
Audrey Rose (Confirmed by bbbbb)
Backfire (Confirmed by hallo-marvin)
Blind Fury (Confirmed by Sidrat)
The Bunker (Confirmed by ateo357)
Children of the Night (Confirmed by ateo357)
Coma (Confirmed by bigdaddyhorse)
Corvette Summer (Confirmed by MickySpoon)
The Deathmaster
The Deer Hunter*
Demon Seed (Confirmed by ateo357)
Don't Tell Her It's Me (aka The Boyfriend School) (Confirmed by T!M)
ELVIS on Tour (Confirmed by Scooter1836)
Eve of Destruction (Confirmed by Sidrat)
The Goodbye Girl (Confirmed by MickySpoon)
Grandmother's House (Confirmed by Sidrat)
Gymkata (Confirmed by ateo357)
King Kong (1976) (Confirmed by bigdaddyhorse)
Let's Get Harry (confirmed by huskersports)
Logan's Run (Confirmed by bbbbb)
Meteor (Confirmed by MickySpoon)
Nice Dreams (Confirmed by RAPMAN)
Night Shift (Confirmed by T!M)
Nightkill (Confirmed by Sidrat)
A Piece of the Action (Confirmed by MickySpoon)
Racing with the Moon (Confirmed by ateo357)
Red Sonja (Confirmed by RAPMAN)
Return of Living Dead part II (Confirmed by RAPMAN)
Skin Deep (Confirmed by ateo357)
Telefon (confirmed by huskersports)
Underground Aces (Confirmed by T!M)

William L. McCaughey (20 titles, 12 confirmed)
1969 (Confirmed by Draxen)
Baby Comes Home
The Big Red One (Confirmed by ateo357)
Bloodstone (confirmed by huskersports)
The Champ
Continental Divide*
Cutter's Way
Dead & Buried (Confirmed by bigdaddyhorse)
Endless Love
Friday the 13th Part III (Confirmed by RAPMAN)
The Jerk (Confirmed by T!M)
The Man Who Loved Women (Confirmed by T!M)
The Osterman Weekend (Theatrical Cut) (confirmed by zwoti)
The Phantom of the Opera
A Streetcar Named Desire
Taps (Confirmed by ateo357)
That's Entertainment (Confirmed by Rizor)
The Wind and The Lion (uncredited, verified by bbbbb)
The Winds of War (Confirmed by MickySpoon)
Zachariah

Bill McCaughey (6 titles, 4 confirmed)
Anatomy of an Illnesss
California Suite (Confirmed by T!M)
Cheech and Chong's Next Movie (Confirmed by RAPMAN)
The Cheap Detective (Confirmed by T!M)
The Osterman Weekend (Director's Cut) (confirmed by huskersports)
The Villain

William Mc Caughey (2 titles, 2 confirmed)
The Chicken Chronicles (confirmed by huskersports)
The Goodbye Girl (Confirmed by ObiKen)

William McCaughy (1 titles, 1 confirmed)
Gorp (confirmed by huskersports)

*Verified by me