I've duplicated and modified the flat rate module for shipment to be used with the Swedish postal service. Now there is a small thing I would like to get working. I want a little description of the shipping method when the customer checks-out and want to choose their shipping method. To give an example:
Posten
Swedish Postal Service 130SEK
This shipping method takes 1-2 working days from the date that we received the product in stock.
The bold part is the text I want added to the module. Now I've looked through the module code and in the .tpl it says "text_description" which I assume is the text description on mouseover, but how do I add text under the shipping option?
I'm pretty new to opencart and I'm thankful if anybody can point me to the right direction

Ps. Not entirely sure if this is the right section, so please move if I posted this in the wrong section.