BB rear main seal retainer

Attempting to do my first rear main seal. Motor is in the car. I believe I have the retainer snugged down correctly but it sits below the pan rail on the block. What am I missing? Thanks, JeffView attachment 1715533913
Attempting to do my first rear main seal. Motor is in the car. I believe I have the retainer snugged down correctly but it sits below the pan rail on the block. What am I missing? Thanks, JeffView attachment 1715533913

Mine was the same way , after numerous times doing it over and over , I bought an aftermarket billet cap , "one of the best thing I `ve done !"
Mine wasnt centered in the block when shoved up on the crank/w/o bolts in it , when I tightened it it pulled it to one side = leak .