were there m18 hellcats and m16 halftracks in the 3rd armored divison or any division

There were no AT battalions organic to the US armored divisions. Most of the armored dividions did have separate AT battalions attached, usually one per division. The same with the self-propelled AT battalions attached to the infantry divisions. You would have to determine which battalions were attached to which division. I believe that the M18 battalions went to the infantry divisions. Sorry I can't be more help. Try a search for M18 Hellcat or for American anti-tank guns, etc.