https://youtu.be/9894Fqsq6T4?si=7TtrWoKYqjJz3bZz
#ChickenboneJohn shows the basics for fitting a combined metal bridge, adjustable saddle and tailpiece to a cigar box guitar. In the comments he gives a link to his website for his own brand UK made metal bridge/tailpieces.
I have used one myself (so far) and they are great!!
Am really happy to advertise a fellow #Brummie in his business selling UK made kit.