Bundling Products With Packaging Changes And Shipping Cost

[jddrillfix]

We at jddrillfix.com manufacture a product that is steel. That being said ordering quantities change the weight and package size very quickly.  With our product the customer is forced to chose a quantity of bushings because the targeted fix is based on "# of row units" 

 

What/How is the best way to go about this?

 

What I want to do:    Customer orders Base Kit, Customer orders the needed amount of bushings to complete desired task, prestashop puts it all together at check out (or sooner) and knows the proper packaging and equivalent shipping variables.

 

thanks in advance

Curtis

 

Edited January 20, 2016 by jddrillfix (see edit history)