Oil Seal on LEV 115-3600033D

Rebuilding a Sears mower engine Model 143.016000, Family YTPXS.1851BA which has been identified as a Tecumseh LEV 115-3600033D and need some help.
Have a really bad oil leak out of the crankshaft seal part 75 in diagram (https://www.searspartsdirect.com/model-number/143006700/0247/1503500.html) and am wonder if when I replace the seal is it set flush to the bottom of the case or is it set down inside the case? Does this make any sense? I have the manual and it says " CHECK TO
SEE IF THE SEAL IS RAISED OR RECESSED. WHEN INSTALLING A NEW OIL SEAL, TAP IT INTO POSITION GENTLY UNTIL IT IS SEATED INTO ITS BOSS. SOME SEALS ARE NOT POSITIONED FLUSH TO THE CYLINDER COVER. Sorry for all caps I am using cut and paste here. I trouble is the seal was replaced about a year ago and was flush to bottom of the case but I am now not sure if that is correct because to oil leakage started after the seal replacement.

I set the seal flush to the case but the is room to seat it a bit lower but I would rather not mess up the seal and gasket by installing it wrong. Any ideas would help.
Tom

The seal on my briggs was recessed about 1/8" or so below the surface of the sump housing. It should have a ledge that it seats on and will bottom out when it is resting on that seat. Just make sure you don't crease the rubber on the seal while sliding the crankshaft into it. I gave the crank a little twist back and forth while sliding it on and it went smooth as butter.
They also make a seal installation tool that will allow you to install the seal after the sump cover is put on, but you really don't need it.
https://www.ebay.com/itm/20Pcs-Car-...over-Installer-Removal-Tool-Kit-/392251609898

Ken

Ken,
Thank you very much, I saw that ledge and was not certain if I should drive the seal down that far. It would put it about 1/8 inch below the case. I have a couple of seal drivers just not THAT tool. Thanks again
Tom