Can category based shipping exclude UPS option?

My client sells two categories of products. One requires UPS shipping and the other requires special handling choices. When the special handling choices are offered, I do not want the customer to be able to select "UPS shipping" (default OC module).

I have purchased "Category Based Shipping" (excellent extension!). However, I can't figure out how to disable UPS shipping on orders that require the special handling/shipping I've defined in the category based shipping module. I need both methods available in the store, but I'd like them to be mutually exclusive.

I assume I'm doing something wrong, but I'm not sure what it is.

Any help would be appreciated.

Shipping methods in OpenCart are independent of one another -- a shipping method cannot affect the availability of another. You would need to use something that modifies core files, such as Restrict Shipping Methods, to limit when each shipping method is available. (Category-Based Shipping has its own category restrictions, so really you'd just need to restrict UPS from appearing based on category criteria.)

Thanks Johnathan. I already use category based shipping (great extension, by the way). However, I think I'll need "Restrict Shipping Methods) too.

One more question: You mention that RSM modifies core files. Does that mean I won't be able to upgrade without breaking things or possibly having to reinstall the extension?

All of my extensions that modify core files use vQmod to do, so you're fine to upgrade OpenCart in the future. (Just remember to re-install vQmod once you upgrade.)

Thanks Johnathan! It is installed and working beautifully. Pleasure dealing with you.