[solved] Different product codes for the same product

I am stuck on this!!!, probably to much time in front of the PC but I can't find an answer to this issue. Sorry if it has been discussed before (to busy and tired to hunt down the answer)

I have "Product A" with three different sizes and each size has it's own Product Code, so far I have managed to get the prices setup for each size but I cannot find how to add the individual codes to each option

PRODUCT A
small-----> a-xxxx-s
medium--> a-xxxx-m
large------> a-xxxx-l

It's not possible in the default OpenCart system without modification.

Never mind I found a way...is not perfect but it would do for the time being!!!

Note: what I did was via the Catalog>Options and added the value and code and then in the actual product I used the Options tab to add the different codes for each size product....I hope it makes sense