Many retainers have a larger gap on one side than teh other. Therfore I don't use side seals. Fill the grooves with Ultra Grey RTV before installing the main seal retainer. Then squesze a little additional in at the top of the groove. Fill the retainer bolt recesses as well. Not all gaskets and pans fully cover that area. Have never had a rear main leak.
Doug
I did similar, only I would add that when I assembled without the side seals like mentioned but dry. Once retainer is installed to fill the sides I used a luer lock syringe and 12ga blunt needle. Worked like a charm to fill up the side seal gaps. Used "Right Stuff" sealant.
