My preference is to coat the outer edge of the seal with white grease before installing it in the groove.  Plain engine oil or bearing assembly lube on the portion of the seal that rides on the crankshaft is a must but white grease can suffice here also. Just don’t install the seal dry.  Offsetting the seal ends at the parting lines also helps the rear seal retaining cap to self align itself so that the seal ends actually butt up to each other.