Hi Woodsguy,
I recommend that you first verify engine timing on this old gal. Simply remove the recoil starter assembly and completely expose the timing belt and flywheel. The flywheel has a "T" stamped in it. With #1 (top) cylinder on compression stroke, align the "T" on the flywheel with the stamped line on the starter support that is between the flywheel and cam pulley.
With the T correctly placed, the dot on the edge of the cam pulley should be facing the T and aligned with a dot mark in the engine case.
Once the timing is correct, you can adjust the valve clearance on #1 cylinder using the adjustment screws on the rocker arms.
After #1 valve lash is properly set, rotate the engine and bring #2 up on top center of the compression stroke and make sure the "T the line and dots are properly aligned. t
Then adjust the valves on #2 cylinder.
The adjustment requires a very small wrench to loosen then tighten the lock nut. I have always used a very small adjustable wrench to do this but care is needed to keep from boogering up the nut.
The clearance on all four valves is 0.002"-0.004". I try to set them all at 0.003" always keeping in mind looser is better than too tight.
If the timing is off or the marks won't stay aligned as the engine is rotated several revolutions then you may need to replace the belt.
I strongly recommend getting a shop manual. You can buy a new one here:
https://publications.powerequipment.honda.com/marine
Or you might find a good used one on ebay or other sites.
The no spark is always a concern for these older outboards because replacement ignition parts are no longer supported by Honda.
I recommend using the NGK spark plugs (DR-5HS) gapped to 0.024"-0.028"
Make sure the point set arms aren't bent or twisted and the contacts come together squarely when closed. The ignition timing 15° before TDC. This is indicated by the "F" stamped in the flywheel.
Align the "F" with the line in the starter case support post used for valve timing. The points should be just opening with the marks aligned and should be the same for both cylinders as they come up on compression stroke. The shop manual describes using a "timing tester" but that's nothing more than an ohmmeter to detect loss of continuity when the points open.