I'm looking to replace the drive shaft oil seal on my 1968 Johnson 3hp. #10 in the Gearcase Group parts catalog. 0327031 - Oil Seal. I have the new seal, but I've never done this before. How do I remove the old seal without doing damage? I've seen that there is a special tool for it in the service manual, but I haven't been able to identify it. Any tips on getting that tool or a different way to get it out would be appreciated. Thanks in advance for any advice.