I'm looking through the unaltered ROM to see what is stored where. (This is incomplete. But I'm posting to keep this intel safe.)

*Units (48AAD to 49255)
--First 10 values - characters (name)
--11th value - HP?
--12th value - Max Fuel
--13th value - Movement Power
--14th value - Loading Limit
--15th value - ? (seems to affect the AI's behavior regarding that unit; I'm not sure)
--16th value - Daily Fuel Lost (applies to air units)
--17th & 18th values - Gold Cost in increments of 100
--19th and 20th values - Materials Cost
--21st value - Weapon 1
--22nd value - Weapon 1 Ammo
--23rd value - Weapon 2
--24th value - Weapon 2 Ammo
--25th value - Unit Category (00 = Armor, 01 = Unarmored, 02 = Air, 03 = Ship, 04 = Submarine)
--26th value - Movement Type (Attacker B gets its own, even though it has the exact same Movement abilities as other planes)
--27th value - Loading Ability (01 = Infantry, 02 = Unarmored, 03 = Air, 04 = Land)
--28th, 29th, and 30th values - Allowed Loading
--Values 31 through 35 - Defense ratings (Armor, Unarmored, Air, Ship, Submarine in that order)
--36th value - base Initiative
--37th value - Initiative lost for each space of movement

*Weapon addresses: 49298 to 494A7 (16 bytes per weapon)
--First 8 values (8-F) - characters (name)
--9th value (10) - minimum range
--10th value (11) - maximum range
--11th value (12) - Armor ATK
--12th value (13) - Unarmored ATK
--13th value (14) - Air ATK
--14th value (15) - Ship ATK
--15th value (16) - Sub ATK
--16th value (17) - cost (Gold)
-Weapons:
--4929/492A - blank
--492A/492B - none
--492B/492C - Machine Gun B
--492C/492D - Machine Gun A
--492D/492E - Gatling Gun B
--492E/492F - Gatling Gun B-4
--492F/4930 - Gatling Gun A
--4930/4931 - Gatling Gun S
--4931/4932 - Grenade
--4932/4933 - Tank Cannon B
--4933/4934 - Tank Cannon A
--4934/4935 - Tank Cannon S
--4935/4936 - Artillery Cannon B
--4936/4937 - Artillery Cannon A
--4937/4938 - Rockets B
--4938/4939 - Rockets A
--4939/493A - Anti-Tank Missile B
--493A/493B - Anti-Tank Missile A
--493B/493C - Bomb
--493C/493D - Anti-City Missile
--493D/493E - Anti-City Bomb
--493E/493F - Surface-To-Air Missile B
--493F/4940 - Surface-To-Air Missile A
--4940/4941 - Surface-To-Air Missile S
--4941/4942 - Air-To-Air Missile B
--4942/4943 - Air-To-Air Missile A
--4943/4944 - Air-To-Air Missile S (unused, most likely intended for the Fighter S)
--4944/4945 - Anti-Ship Missile
--4945/4946 - Direct Torpedo
--4946/4947 - Torpedo
--4947/4948 - Supplies
--4948/4949 - Materials (no room for listing Materials price of 1)
--4949/494A - Air-To-Surface Missile

*Text (names, mostly Katakana anyway, most are guesses but should be right):
-01 - WO
-02-06 - no consonant
-07-0B - K
-0C-10 - S
-11-15 - T
-16-1A - N
-1B-1F - H
-20-24 - M
-25-27 - Y
-28-2C - R
-2D - WA
-2E - N'
-2F-33 - G
-34-38 - Z
-39-3D - D
-3E-42 - B
-43-47 - P
-48-4C - small vowel
-4D-4F - small Y
-50 - small TSU
-51 - dash
-8B-A4 - English alphabet
-A7 - dash

*Medal names - 51FED to 52148 - 348 bytes
*Medal descriptions - 52149 to 52322 (hidden Medal is 52323 to 52330) - 474 bytes (14 bytes for hidden medal)
*Beginner/Standard Mode Mission Specs - 94BCB to 95C14 (Mission specs for Standard is 95BE0 to 95C14) - 4170 bytes (36 bytes for Standard)
*Unit Category text - 95E53 to 95E7A - 40 bytes
*Individual unit information - C993C to CAFE2 - 9899 bytes

Map data starting point:
*Demo 02 (plays if left on the title screen long enough the second time) - A4000
*Ball Island (S1) - A41F2
*Practice 1 - B066F
*Practice 2 - B082E
*Practice 3 - B09F9
*Practice 4 - B0BCA
*Practice 5 - B0D98
*Practice 6 - B0F5A
*Practice 7 - B1125
*Practice 8 - B12EA
*Practice 9 - B14B2
*Practice 10 - B167A
*Practice 11 - B1842
*Practice 12 - B1A0D
*Practice 13 - B1BDB
*Practice 14 - B1DA3
*Practice 15 - B1F6B
*Practice 16 - B2133 (to B2303)
*Tirage Peninsula (C1) - B4000
*Nidohegun Island Plan A (C45) - BF394 (to BFA70)

The name is after the first 32 bytes. The last 2 numbers before the data for the terrain are the map size. Then after that, the next x numbers where x is the product of the 7th and 8th numbers is the terrain data from left to right then top to bottom. If there isn't an FF immediately, there should be a multiple of 3 numbers, 3 for each predeployed unit: the first one to determine X coordinates (from the leftmost column), the second to determine Y coordinates (from the topmost row), and the third to determine which unit it is (divide by 2, rounding down to determine which unit it is, and the remainder is for which side; even numbered units will be Red Star while odd numbered ones will be White Moon)

Terrain:
*Red Star HQ - 01
*Red Star City - 02
*Red Star Factory - 04
*Red Star Airport - 06
*White Moon HQ - 0C
*White Moon Factory - 0F
*Neutral City - 17
*Neutral Factory - 19
*Ruined Factory - 1A
*Plains - 20
*Road - 21
*Mountain - 24
*Forest - 25
*Wasteland - 26
*Desert - 27
*River - 28
*Sea - 29
*Beach - 2A

JP Text (dialogue):
60 - wo
61-65 - no consonant
66-6A - k
6B-6F - s
70-74 - t
75-79 - n
7A-7E - h
7F-83 - m
84-86 - y
87-8B - r
8C - wa
8D - n'
8E-92 - g
93-97 - z
98-9C - d
9D-A1 - b
A2-A6 - p
A7-AB - small vowel
AC-AE - small y
AF - small tsu

B0 - WO
B1-B5 - no consonant
B6-BA - K
BB-BF - S
C0-C4 - T
C5-C9 - N
CA-CE - H
CF-D3 - M
D4-D6 - Y
D7-DB - R
DC - WA
DD - N'
DE-E2 - G
E3-E7 - Z
E8-EC - D
ED-F1 - B
F2-F6 - P
F7-FB - small vowel
FC-FE - small Y
FF - small TSU

Space

More space

One more for the road.

Sweet, you found the text! Now a GBW3 translation wouldn't be too far off with the English font already in there. Awesome.