if i was to change it on mine i would have to unbolt the transmission, remove the flywheel, drop the
oil pan, take off the rear 4 bolt cap, and squeegie it in between the block and crank then reinstall the main cap. if i was unable to fit it between the block and crank i would have to drop the crank slightly by loosening the other caps.
the seal is a one piece affair and there is quite a bit of squish when the cap is installed so i don't know if you'd be able to insert it without dropping the crank.
that would have have to be some leak.
if you do replace it cv products sells a seal for dry sump engines that has double lips that would be the one to use. i have the part # in the shop if you decide you want to bypass cv products, they are slightly expensive.