Think Penzance is still a large lever frame. I know some of the boxes on the Cornish mail line have frames for their stations and then nx panel in addition.
I’m sure Worcester Srub Hill SB & Worcester Tunnel Junction SB are both Grade 5.
Llandudno Junction and Holyhead are both Grade 5 as well I think, nothing now in South Wales over a grade 3 or at most 4.
Cornish SB beyond Plymouth are tops Grade 4, Penzance being a NX panel in a traditional SB though.