Ensure it replaces MP5 for the mod to work.

First, with SparkIV, export your WEAPONS.ivaud from resident.rpf (find it in
pc\audio\Sfx). Open the WEAPONS.ivaud with GTA IV-aud and import all sound files
to here (match the names):

MP5_SHOT1_L
MP5_SHOT1_R
MP5_SHOT2_A
MP5_SHOT2_B
MP5_SHOT2_C
MP5_SHOT2_D

Save once done and import back to resident.rpf, Save and close.

Now install the new WeaponInfo to MP5 line below:

	<weapon type="MP5">
		<data slot="SMG" firetype="INSTANT_HIT" damagetype="BULLET" group="SMG" targetrange="90.0" weaponrange="400" clipsize="25" ammomax="250" timebetweenshots="75">
			<damage base="15" networkplayermod="2.5" networkpedmod="1.25"/>
			<physics force="20.0"/>
			<reload time="2266" fasttime="2266" crouchtime="2000"/>

			<aiming accuracy="0.6">
				<offset x="0.13" y="1.0" z="0.45"/>
				<crouchedoffset x="0.11" y="1.0" z="-0.02"/>
				<reticule standing="0.75" ducked="0.6" scale="0.3"/>
			</aiming>

			<pickup regentime="360000" ammoonstreet="60"/>

			<controller>
				<rumble duration="100" intensity="0.02"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>CAN_AIM</flag>
				<flag>2HANDED</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
			</flags>
		</data>

		<assets model="w_mp5">
			<anim group="gun@mp5k" meleegroup1="firearm_core">
				<rates firerate="1.6" blindfirerate="1.6"/>
			</anim>
			<effects>
				<muzzle fx="muz_smg"/>
				<shell fx="weap_ejected_smg"/>
			</effects>
		</assets>
	</weapon>