Low order fee by manufacturer?

how can i set this to look at another column in the products table, i am able to set up products by the way they ship. i have Shipper as a column and want to look at that to determin low order fee.
would i change, $chk_manufacturers_1_id = 2; // Crain Cutter
to $chk_Shipper_1_id = Crain; // Crain Cutter

i changed all instances of manufacturers to Shipper and changed the id number to my value and all seems to be working.

Good Afternoon, I was looking for something exactly like this, it is possible to see the complete modified file working, since I tried to make the indicated modification, but it doesn't work for me, how did you also manage the module configuration tables? Thank you