Display old price & price reduction in any module - manual

[lipo999]

Dears all,

I have module - additional product in cart (cross selling module).

I would like display old price and price reduction (this module does not displaying), only final price.

Can you someone tell me, what must be edited to display it? 

Some controller + tpl file 

I find some threads here for e.g. block viewed products, but its confuse.

 

Thank you all for advice.