One on each starboard and port as is standard.
None of them ever had a support and to access the spaces, you had to use one hand to hold the lid or risk the lid slamming shut on you.
This week I found a fantastic product made by Moonlight Marine.
I bought the 2 my West Marine had in stock and I will get another.
You install them to support the lid in the fully open position. To close the lid you bend the spring and the hatch will close. When in the open position, the spring is rigid and can firmly hold a good deal of weight.
Here are some installation photos...
