Basically if u look in the MIM at the invetory files or w/e find the skint that you want then look at what the image number is then i think u take 1 away from it and then put that in your database as its 'looks'.
Then repeat the same for the weapon looks on outside and this is in the 'Shape' section of ur database. But hsapre number works diffrent, each diffrent set of shapes is classed as 1 so you have to count up at what number shape it is. hope this helps