Each product option has its own SKU

I have been using a custom mod to do this in OC 1.5x, however it is not available for 2.0. I would like to be able to assign a different SKU to each product option and have the it replace the model # shown in the shopping cart depending on which option is picked. For example Product XXX has 2 options Large and Small. Large option has SKU #1234 and Small option has SKU #4321. Thanks. I love OpenCart. So easy to use and the code is so accessible!

Can I have a look at your current extension so I may be able to rewrite it to work with OpenCart 2.0.x