Dirk
We have just completed a re-instrument of Sandack (P325 #30) and have run a large number of cables, including a Raymarine VHF 2nd station cable with chunky connectors from the chart table to the stern of the boat. We took the route from the instrument panel above the chart table, straight down and then aft, through the space under the port saloon seat and then behind the battery box and into the space below the sink. We then ran it from below the sink, under the cooker and into the port aft cabin space alongside the existing wiring loom. If this sounds like a nightmare then you are not far from the truth. What made it possible was the use of a wireless endoscope, £40 from Amazon, to find the route and then pull back a messenger cord.
https://www.amazon.co.uk...e%2Caps%2C108&sr=8-7
I did have to use a hole saw to open up some of the wiring passages through bulkheads a little but it all worked. Without being able to see the path though, frustration may have led us to use a visible cable run which we didn't want.
Top tip 1. pull a second messenger line with your VHF cable and leave it in place for future use.
Top tip 2. The endoscope is the best buy we have made. Use it for inspecting inaccessible bilges under the heads floor, for retrieving objects dropped into tiny spaces, for inspecting the ram anode part way through the season and for terrifying the ship's cat. It works well on Android but you'd need to check Apple.
Best of luck
Ewan