Easypopulate Error message

[fuzzyphil]

We have been experiencing some rather bizarre problems of late with our website so I figured the best course of action was to go back to square one. So I have loaded a fresh copy of max1.7 on my localhost.
I am trying to import all my data across from my working site using easypopulate but I keep getting stuck with the same error message when I try to upload the files into the fresh max1.7.
Please could somebody advise where I should be looking to fix this error.

16Lights - Ft & Rr... ERROR! - Too many characters in the model number.
12 is the maximum on a standard OSC install.
Your maximum product_model length is set to 15
You can either shorten your model numbers or increase the size of the field in the database

It refers to maximum product_model length is set to 15 which sound self explanitory but I am having one heck of a job finding the relevant field inside the sql database to make the adjustment.

Some guidence would be gratefully received please.
Phil.