new to boating , need help !

I am putting together an old runabout , I have a functional 1974 115 Evinrude Model #115493b , that has not been ran in as near as I can determine 7 years ! Everything I have read says I need to change the water pump impeller , I can not find how to remove the shift linkage ? Mine does not have a "belcrank" , not anything like that , it has a split linkage about 4 inches long with no obvious way to remove from the shift rod ? any help would be greatly appreciated !
Thanks

You need a 5/8" combination wrench.--------Now find the bolt with the 5/8 head on it.----It is on the starboard side behind the lower carburetor.----Loosen that bolt till you can spread those 2 arms to release the shift rod.-------Nothing to it at all.

Thanks , I thought about that , but I wanted to ask someone before I broke something , LOL !!!!

I didn't know any of that needed done , had it running in about 10 minutes after I got it LOL ! runs fine acts like it may have a plug fouling a little , water pump in it is working , just thought i'd replace it .
Thanks

New to boats , this is a learning experience lol ! I don't have much in either one ,$524.00 in both before any parts . I have worked on a lot of bikes , pretty similar just the water pump was bothering me it seems to work fine at the moment .I tried to upload pics must have been too big or something ?

Well, I got the pump installed , and the rest of the boat kinda together , took it out for its "maiden voyage" It didn't sink ! lol !! Didn't want to idle in the water ? I had earmuffs on it at home . Didn't expect a difference ? but I turned it up some and we went on our way . runs fairly well , it kinda pulls to the left ? top speed is about "33" according to the speedo , how accurate are these things ? It is a 14 foot i guess tri-hull ? I figured a 115 would do a little better . pretty uneventful day till it suddenly ran out of fuel !! what should the cylinder pressure be on this old engine ? i'll pick up a gauge and check it . when I pull the starter rope they feel uniform . what issues would any low pressure cause ?

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