linkHi,
I am referring to the picture below. I made a cable with RCA to dual SCART. This allows to get analogue audio from the new TV/Panel and provide the input to the AV scart and the V.TAPE scart of the BV5.
If your BV5 does not have any scart sockets I assume it's not a European version. I assume you'll have other connections for AV, V.TAPE and DVD. If they are RCA sockets it makes life easier. No soldering will be required.
I use the TT455-RT-238 from Lintronic. I soldered a minijack cable, which is plugged into the TT455-RT-238, to the original IR eye of the BV5. Only ground and signal. Do not solder power. It will get the power from the BV chassis. Some technical flair is needed to configure the TT455-RT-238.
You could make a test with any TV and make all the connections to the BV5. Check if it behaves as you’d expect. Changing source, volume etc. etc.
Before taking the BV5 apart. Remember to setup stand position, connections and other stuff in the MENU before removing the original panel. You’ll lose access to this menu unless the new TV will accept the VGA signal from the BV5 chassis. I got access to the internal VGA cable and I kept the original panel. If I should ever need to access the menu it will be possible.