Head installation access

[c2cSailor]

So I decided to buy a new head. But I don't understand how to gain access to the nuts or whatever is holding the bolts in place on my Groco head in my Catalina 27. Can anyone shed some light? One of the mounting bolts has just recently started pulling up through the fiberglass.

[HerbDB]

I just replaced the Jabsco compact head in my boat last week. It was actually secured with four lag screws. No backing plate or nuts to access. Easy replacement, four screws and two hose clamps. Much easier than rebuilding pump and not much more expensive.