Re: 40 hp '69 Evinrude flywheel
Harmonic balancer puller, Harbor Frght for ~ $10 or from any auto parts place and use gr 8 bolts and washers. You will also need a fly wheel holder ( a good tool available from NAPA as a fly wheel turner for < $30) Do NOT pry under the fly wheel to get it off, BC you'll probably be in for a new fly wheel.
BTW, the fly wheel nut MUST be torqued to the correct value when re-installing. Check your shop manual for the correct value.