Using the Tools ... Developers Tool Kit ... with a search in the bottom input box on:
shipping weight
and selecting Catalog ... and clicking SEARCH ... I come up with:
/includes/languages/english/product_info.php
Line #17 : define('TEXT_PRODUCT_WEIGHT', 'Shipping Weight: ');
Searching on:
lbs
I come up with:
/includes/languages/english.php
Line #391 : define('TEXT_PRODUCT_WEIGHT_UNIT','lbs');
Line #394 : define('TEXT_SHIPPING_WEIGHT','lbs');
See if those help you on using the templates and overrides to customize your site ... :smile: