e-way bill for Job Work - Goods and Services Tax - GST

In W.B. activity of movement for Job Work was totally exempted from issuing e-way bill. Now w.e.f. 01.12.2023, it is required for consignment value above Rs.50,000. On the delivery challan. we are mentioning the description and HSN code of the product emerging from job work, giving the value of the material and mentioning GST rate which is 18% for the concerned HSN. While raising our invoice for job work charges, we are mentioning SAC code and the GST rate which is 12%. Our principal is asking us to mention the GST rate in the delivery challan as 12% since we are charging the same in our invoice. Kindly advise the correct procedure.