Yamaha 70hp beto engine

[57paulimo]

Hi, I'm REALLY struggling with a water pump impeller change on the above engine.
I hope someone has had this particular headscratcher before.
I managed to drop the lower end off, even with two rounded bolts. I noticed a rubber strip just in front of the water pump housing that didn't look in great shape, so I brought up my manual on the laptop, but........... nothing, no mention of this piece of rubber.
I sent an email off to Pacer Marine, who informed me its a Rubber Damper Seal, which stops exhaust gases escaping!
My question, which way does it go round? It can with a small L shaped bracket, which ive put in first with the rubber damper on top.
I can't find reference to this on Youtube anywhere!
Any help would be most welcome.
Thanks in advance.[emoji848]

[phantom 19]

L piece goes in first. There are two rounded corners to the rubber seal should be fairly obvious which way it sits in the L piece / gearbox casting.

[57paulimo]

Many thanks for your reply Phantom.