Thanks guys, I am a rank amateur at this but seek advice from an international group of restorers. I am just glad I didn't see this until I was well underway or I might not have tried to do it.
"This has to be one of the ''most far gone'' horses I have ever seen. If the components were sound in themselves it would be very different, but it looks like a heartless task, so many splits and cracks in the actual blocks.. It would have to be a labour of love...but most woodworkers would want good money for taking this on!"
Just got to love blissful ignorance