Help in editing a LUA script

[ViRuSLN]

Hey community, I'm using a script called weapon-stid which adds the weapons on the back of the player, I want to know how to change the position because I'm using a modded skin and the weapons are not exactly on the back of this skin, so by which way I can change this? I dont know anything in scripting or coding so please help 

addEventHandler("onClientPreRender",root,function()
	for k,v in pairs(jugadores) do
		local x,y,z = getPedBonePosition(k,3)
		local rot = math.rad(90-getPedRotation(k))
		local i = 15
		local wep = getPedWeaponSlot(k)
		local ox,oy = math.cos(rot)*0.21,-math.sin(rot)*0.21
		local alpha = getElementAlpha(k)
		for q,w in pairs(v) do
			if q == wep then
				destruirArma(k,q)
			else
				setElementRotation(w,0,70,getPedRotation(k)+90)
				setElementAlpha(w,alpha)
				if q==2 then
					local px,py,pz = getPedBonePosition(k,51)
					local qx,qy = math.sin(rot)*0.11,math.cos(rot)*0.11
					setElementPosition(w,px+qx,py+qy,pz)
				elseif q==4 then
					local px,py,pz = getPedBonePosition(k,41)
					local qx,qy = math.sin(rot)*0.06,math.cos(rot)*0.06
					setElementPosition(w,px-qx,py-qy,pz)
				else
					setElementPosition(w,x+ox,y+oy,z-0.2)
					setElementRotation(w,-17,-(50+i),getPedRotation(k))
					i=i+15
				end
			end
		end
		if info[k][1] and not info[k][2] then
			for i=1,7 do
				local arma = getPedWeapon(k,i)
				if arma~=wep and arma>0 and not jugadores[k][i] then
					crearArma(k,arma)
				end
			end
		end
	end
end)

 

Link of the script: https://community.multitheftauto.com/index.php?p=resources&s=details&id=3726