The importance of measuring bell housing runout.

I don't think you have to do anything other than write down what your runout is and send it to SST in order to stay in warranty.
Silver Sport has a work sheet in the link below you fill out and submit. They want initial reading, offset dowels used, orientation of offset dowels, and final readings:

https://www.shiftsst.com/product_images/shiftsst/installation_instruction-instruction_file-83-v3.pdf