Turreted SHP vehicles cannot be repaletted by using Palette=

Palette= doesn't work on turreted SHP units.

##### STEPS TO REPRODUCE #####
Copy-paste Titan's code and SHP from Tiberian Sun (attached to this report) OR set Terror Drone to Turret=yes and attach a Palette to it.

Titan's code:
[MMCH]
Name=Titan
WalkRate=2
Image=MMCH
Prerequisite=GDIFACTORY
Primary=120mm
Strength=400
Category=AFV
Armor=heavy
Turret=yes
IsTilter=no
;TargetLaser=yes
TooBigToFitUnderBridge=true
TechLevel=3
Sight=8
Speed=4
CrateGoodie=yes
Crusher=yes
Owner=GDI
Cost=800
Points=25
ROT=5
Explosion=TWLT070,S_BANG48,S_BRNL58,S_CLSN58,S_TUMU60
VoiceSelect=25-I000,25-I002,25-I004,25-I006
VoiceMove=25-I012,25-I014,25-I016,25-I018,25-I022
VoiceAttack=25-I014,25-I022,25-I024,25-I026
VoiceFeedback=
MaxDebris=4
Locomotor={55D141B8-DB94-11d1-AC98-006008055BB5}
MovementZone=Destroyer
ThreatPosed=40 ; This value MUST be 0 for all building addons
DamageParticleSystems=SparkSys,SmallGreySSys
DamageSmokeOffset=100, 100, 275
Weight=3.5
Accelerates=false
ZFudgeColumn=8
ZFudgeTunnel=13
EliteAbilities=SENSORS

Art:
[MMCH]
Voxel=no
Remapable=yes
Cameo=MMCHICON
PrimaryFireFLH=0,-50,100
PBarrelLength=250
SBarrelLength=250
TurretOffset=0
WalkFrames=15

##### ADDITIONAL INFORMATION #####
Splitted from 172.

Probably because unit turrets don't have art entries. Building turrets must be defined in the art entry at the same place Palette is defined, and they works.