Re: replace control cables 1985 johnson 70hp
The easiest way to learn is to pick-up a manual. It'll cost money up front but the savings will far surpass the cost when you're able to do accomplish work such as the link-n-sync, lower unit oil change, etc.
But to adjust the cable you hold the linkages on the motor "centered" (there will be free play in the linkages) then turn the adjustment knob on the cable to match the linkages. Don't adjust the linkages to meet the cables. That'll defeat the purpose of the link-n-sync.
EDIT: Forgot to add. That procedure is for your shift cable. I'll let someone else post how to adjust the throttle lever cable. But if it's anything like my 90hp, ensure the throttle lever is as far back as it will go (without making any adjustments to the idle screws, etc) then adjust the cable accordingly to fit.