Re: 1983 70 Merc shift-shaft...
You should be able to undo the four bolts and one nut on the lower unit, 4 just above the cavitation plate and a nut either under the trim tab or just forward of it. (My 87 has it just forward of the tab) The lower unit should then drop off, maybe with the help of a rap with a wooden block. The shift linkage slider just forward of the water pump should slide out with the lower unit. No need to beat roll pins out. Get your serial number and go to mercurypartsexpress.com and look at the parts break down for your lower unit
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