Utmost Savagery by Lt Col Alexander is the best resource I know for the OoB of the Amphib Corps as it entered the Tarawa Atoll that November. His research is impeccably accurate and well done on this point. History of USMC Operation in WW 2 ( The red books) list the following...
2nd Mar Div as of Nov 1st, 1943 was as assigned by HQMC to consist of the following units, and to be committed to the battle in Operation Galvanic :
"APPENDIX G
Marine Task Organization and Command List
MARINE GROUND UNITS
A. GILBERT ISLANDS2
(13 November-8 December 1943)
V Amphibious Corps
(20-25Nov43)
CG MajGen Holland M. Smith
CofS BGen Graves B. Erskine
C-1 LtCol Albert F. Metze
C-2 LtCol St. Julien R. Marshall
C-3 Col Peter P. Schrider
C-4 Col Raymond E. Knapp
V Corps Headquarters and Service Battalion
(20-25Nov43)
CO Maj Thomas R. Wert
V Corps Reconnaissance Company
(18Nov-3Dec43)
CO Capt James L. Jones
2d Airdrome Battalion
(21 Aug-8Dec43)
CO LtCol Thomas G. McFarland
2d Defense Battalion
(24Nov-8Dec43)
CO Col Norman E. True
5th Defense Battalion
(2Oct42-8Dec43)
CO Col George F. Good, Jr.
8th Defense Battalion
(28Nov-8Dec43)
CO Col Lloyd L. Leech
25th Replacement Battalion
(13Nov-8Dec43)
CO Maj John H. McMillan
Headquarters, 2d Marine Division
(20Nov-4Dec43)
CG MajGen Julian C. Smith
ADC BGen Leo D. Hermle
CofS Col Merritt A. Edson
D-1 LtCol Cornelius P. Van Ness
D-2 LtCol Thomas J. Colley
D-3 LtCol James P. Riseley
D-4 LtCol Jesse S. Cook, Jr.
Division Headquarters and Service Battalion
(20Nov-4Dec43)
CO LtCol Lyman G. Miller
Division Special and Service Troops
(20-24Nov43)
CO Col Robert C. Thaxton
2d Amphibian Tractor Battalion
(20Nov-5Dec43)
CO Maj Henry C. Drewes (KIA 20Nov43)
Maj Henry G. Lawrence, Jr. (from 20Nov43) (WIA 20Nov43)
2d Antitank Battalion
(20-30Nov43)
CO Capt Saul Glassman
2d Medical Battalion
(20-24Nov43)
CO LCdr Justin J. Stein, MC, USN
2d Service Battalion
(20-24Nov43)
CO Col Clarence H. Baldwin
2d Special Weapons Battalion
(20-24Nov43)
CO Maj Guy E. Tannyhill
2d Tank Battalion
(20-24Nov43)
CO LtCol Alexander B. Swenceski
(WIA 20Nov43)
2d Marines
(20-24Nov43)
CO Col David M. Shoup
ExO LtCol Dixon Goen
R-3 Maj Thomas A. Culhane, Jr.
1st Battalion, 2d Marines
CO Maj Wood B. Kyle
2d Battalion, 2d Marines
CO LtCol Herbert R. Amey, Jr.
(KIA 20Nov43)
Maj Howard J. Rice (from 20Nov43)
3d Battalion, 2d Marines
CO Maj John F. Schoettel
6th Marines
(20Nov-8Dec43)
CO Col Maurice G. Holmes
ExO LtCol Russell Lloyd
R-3 Maj Loren E. Haffner
1st Battalion, 6th Marines
CO Maj William K. Jones
2d Battalion, 6th Marines
CO LtCol Raymond L. Murray
3d Battalion, 6th Marines
CO LtCol Kenneth F. McLeod
8th Marines
(20-24Nov43)
CO Col Elmer E. Hall
ExO LtCol Paul D. Sherman
R-3 Maj Hewitt D. Adams
1st Battalion, 8th Marines
CO Maj Lawrence C. Hays, Jr.
(WIA 22 Nov43)
2d Battalion, 8th Marines
CO Maj Henry P. Crowe
3d Battalion, 8th Marines
CO Maj Robert H, Ruud
10th Marines
(20Nov-1Dec43)
CO BGen Thomas E. Bourke3
ExO LtCol Ralph E. Forsyth
R-3 LtCol Marvin H. Floom
1st Battalion, 10th Marines
CO LtCol Presley M. Rixey
2d Battalion, 10th Marines
CO LtCol George R. E. Shell
3d Battalion, 10th Marines
CO LtCol Manly L. Curry
4th Battalion, 10th Marines
CO LtCol Kenneth A. Jorgensen
5th Battalion, 10th Marines
CO Maj Howard V. Hiett
18th Marines
(20-24Nov43)
CO Col Cyril W. Martyr
ExO LtCol Kenneth P. Corson
R-3 LtCol Ewart S. Laue
1st Battalion, 18th Marines (Engineer)
CO Maj August L. Vogt
2d Battalion, 18th Marines (Pioneer)
CO LtCol Chester J. Salazar
3d Battalion, 18th Marines
(18th U. S. Naval Construction Battalion)
CO Cdr Lawrence Emerson Tull, CEC, USN" (1)
(1) History of U.S. Marine Corps Operations in World War II, Central Pacific to Saipan, Vol III Pgs 619-622
Now you can see the entirety of the assigned forces. the resource document there is available online at hyperwar on the Web, and the preceding appendix to this one lists the starting locations of each of the sub - units ( ie. where they embarked and sailed from and where they met th Galvanic Force at en route.)
This was a mish mash of units not trained to work as a large amphibious force yet. For an example, Lt Hawkin's detachment and the rest of that convoy did not meet up with the rest of the division until the Galvanic convoy from New Zealand passed New Ireland and stood several miles off Kaveing.
You can compare the above to the BLT rosters and schedules and see what is "still afloat" during those 76 hours of battle.
KRL, Jon H