2001 Bavaria 47 - size of aluminum plate below clutch set

[UP]

Hi,

I'm working on modifying (replace/add) the original clutch set on my 2001 Bavaria 47 Cruiser. The original (?) clutch set are Rutgerson RC75, a 3-block and single. To my understanding, there is an aluminum plate molded between the deck and the cabin ceiling, right below the clutch mounts, into which the clutch base plate screws fasten.

Does anyone have more specific information regarding the size (extent) and thickness of the plate? I'm considering upgrading to a larger clutch (the Rutgerson RC120) for ease of operation, plus it has aluminum handles. This will require drilling and tapping new holes, but I'd like to stay in limits of the plate - and would like to avoid cutting a hole in the aft cabin ceiling to find the size of the plate.

PS - below is attached an image of my partially removed RC75 clutch base plates.

Thanks!

[Yngmar]

Try a stud finder: https://www.ebay.co.uk/itm/404539779136

Should be able to map out the area the plate covers. We had removable ceiling panels so it was easy to see from below. The plate on ours was much larger than the clutch area.

[UP]

Good tip @Yngmar. I have that tool at the office, will check the deck area with it and post back here for future reference.

[UP]

I took the stud-finder to the deck of the 2001 Bavaria 47 cruiser and here are the results (in SI units):
With safe margins (where the stud finder was giving a maximum amplitude signal), the aluminum plate measures 15x30 cm, where 30 cm measures along the long axis of the boat and 15 cm along the short axis of the boat starting from the cabin hatch edge.

The attached images below explain where the plate is. The plate is below the red outline in the hazy-superimposed image.

[kavok]

I have 14 cluthes now. Two of them remain out of the alluminio plate.
Screws, big washers and nuts.
I opened from the inside the countermould.
Boat 40 Cruiser my 2008.
Job to do with great precision.
I do not use none of old holes.