Oily residue in 175hp Sport Jet port side exhaust chamber

[Stomp10]

While reassembling the snoot on my jet, I happened to notice that the port side exhaust chamber had an oily residue film, while the starboard side is dry.
How concerned should I be about this?
Last time it ran was in the driveway, on the hose last fall. It ran good for the brief test drive prior to that.
I have picked up a cheapo endoscope, thinking I may be able to get a look at my reed valves to see if they are stainless or composite material with only having to pull the carbs off.
Now I am thinking that it may be prudent to take a look at the bottom 2 cylinders, just to be safe...
This wasn't in the plan for the springtime (now early summer) startup, dadgumit!
So, just looking to source opinion from the experts here.
Outside of the residue, it sounds and runs good.
I'd like to get it out on the water this season without a lot of fuss but I also don't wanna blow it up either.
Opinions?

Edit-I think I'm answering my own questions here on how to proceed but, still would value anyone's input.
Pulling plugs and compression test coming up.....
Might do the endoscope thing too.

 

[Stomp10]

A video of endoscoping the bottom left cylinder:

 

[Stomp10]

A clearer head on cam view of the bottom left cylinder:

Its not as bad as I expected. The spark plug was just over finger tight too.... plug was oily.
Anyone want to take bets as to if it will make it through the season?

 

[kaylix]

Did it make it through the season?

 

[Stomp10]

Heh no, cuz I decided to replace the engine and all engine electrics, plus a new flywheel.
Also need to replace this mess behind the shift\throttle control:

I am having some physical challenges with the body contortions needed to get this done on account of the fact I'm just not as young as I used to be.
I finally found a guy that will do this, and take it the rest of the way home for me.
Hopefully this Thursday to take it in.
New seats are in and after he's all done working on it, this resto is still only partially done.
I still need to give the bottom side a good cleaning and replace the graphics on the sides.
Then it will be all done.
I can't wait!

 

[kaylix]

Keep us posted, best of luck!