[SignTorch]

there may be a better way, but this worked for me

to hide the weight, using custom skins module

copy skins\default\en\product\details\common_attributes \common.product-attributes.weight.tpl

to skins\custom_skin\default\en\product\details\commo n_attributes\common.product-attributes.weight.tpl

and comment out the template code

{* 
<li IF="!getWeight()=0">
  <div><strong>{t(#Weight#)}</strong></div>
  <span>{formatWeight(getWeight())}</span>
</li>
*}

I'm not using inventory, so I'd guess for inventory maybe do the same with this template

skins\default\en\product\details\parts\common.stoc k.tpl