Mercury 4hp 2stroke outboard gearbox top up

[knocker8]

On you tube videos it shows 2 screws. One to drain the oil and one for the top up level. My engine does not have these screws so what is the top up process and with what

 

[makomark]

FWIW, you'd likely get more thoughts if you would have posted in the mercury outboard section....

That said, I've never seen a mercury without the two screws in the gear housing...one down low on the bulge where the prop shaft goes and the other up high above the anti cavitation plate...