Les Paul build -Hugh

[DrNomis_44]

Cheers Dr. Nomis
I downloaded Infraview but the laptop died recently so I'm using the iPad
The 'feedback' issue is more of a buzz or hum when the guitar is plugged in, could it be an earthing problem I wonder??

It does sound like an earthing problem to me, does the hum go away if you touch the strings, if it does, try using a multimeter to check if there's a ground connection between the bridge and a convenient ground point, such as the back of one of the volume controls or the sleeve connection of the output jack.