Ray Lumley M100 tube amps

My friend is using a pair of Lumley mono blocks to drive the original VR4 speakers and using an original Conrad Johnson pre amp from the 1970's.Talk about retro sound.
I can't remember the model number of his Lumleys, but they use 4 KT88's a side and have beautifully engraved casework which almost looks like it's made of smoked glass.
I sold him one of his 2 sets of Grant Lumley amps that were very nice sounding el34 amps which he was running biamped on the VR4's before he got the bigger amps.
I was told the great Lumley sound was because they used(sowter?)great transformers.
Enjoy them, they keep on running year after year.

My friend with the M75 Lumley has had one amp shut down.
Before that he had some crackling,static sounds,then silence.
We checked all the tubes and they were fine, but the 500MA fuse is toast.

I've been trying to source a schematic or manual for him,but no luck,which seems par for the course.

If anyone has a manual or schematic and could send a copy , please contact me, as I would like to help my friend out and get the music playing again.