Maruyama pole chainsaw not oiling, trying to take apart , need advice.

[StihlMaster88]

I have a Maruyama MC261/321 powerhead which is for a multicutter system. The pole chainsaw I believe should be a MC-Ps10/11 or MC-PL10/11 . It's not oiling so I'm trying to get down in to the gears but I'm clueless on out to get the rim sprocket gear out. I can't find a good picture of the part to see if it's splined or screws in and since it's an older and odder machine there is little info on it. I'm going to call tech on monday but I'm trying to get at it right away .I'll attach some pictures and a link from the maruyama website of the part I'm working on. you'll have to scroll down and its part #50 on page #17 https://maruyama-us.com/wp-content/uploads/2011/05/MC260261321-Multi-cutter-Attachments.pdf