I have a number of these motors for parts.---Memory tell me there are more than 3 screws on the lower cowling.---Possibly 4 and some pins , these covers come off quite easily.
Hinge ?---Cover bolts go right to the powerhead ??
If you understand the concept of " thermal expansion " then this might be easy.-----Use heat to get this pin out.------Heat will open the hole in the block and the pin may fall out !!!