B473 Dripless shaft stuffing box seacock replacement question

[Glide2277]

11:30 AM (less than a minute ago)

Hi all

so, i have never owned a boat with 'dripless' stuffing box-until now- 2005 Beneteau 473.  I presume that the cooling water enters through a seacock and then exits through another cock..I want to replace the existing sea cock with a Groco Flanged Adapter and a ball valve (about 1/5 the price of a new sea-cock and still silicone bronze)--as described by Clark Beek in Sail Feed.

https://www.sailfeed.com/2013/10/no-nos-and-good-practice-with-thru-hulls-and-seacocks/ds

.Unfortunately i am back in the USA and my boat is in Athens...so I can't look at the arrangement right now, and lost the pictures i took of that area of the boat...

Does anyone know the diameter of the intake sea cock thru-hull and the output so i could buy the parts here before i head back to Greece?

I wonder about replacing the entire thru-hull portion, or just add a flanged adapter and ball valve as described in the above article?  Should I buy a thru-hull piece as well--any thoughts about plastic thru-hulls and bronze adapters...sorry if i have this completely wrong!

Thanks all

Max