Well after replacing a lot of resistors around Q205, Q206, a and few transistors that were rusted in to their sockets(the sockets were removed too but not replaced) it now has video!
I had to mess with the AGC and fine tuning to get it, but it is there!
I still need to address the dead color circuitry, and the BAD vertical jitters which video has now revealed, but I'm very happy to have gotten this far. The vertical hold control is at the end of it's range, and despite being sort of locked for most of the photo op it was bouncing rapidly the whole time.
I never thought I'd be working on a set with PCBs and transistors together until I got this one, and after working on the SS mono video chain I'm starting to miss working with good old terminal strips and tubes.