Dear Jez,
I did know that the actually Troughline was made cheaper in the Tr II onwards. If you look at the point to point, it is also far neater than later variants, where the added complexity seems to have completely defeated any possibility of a clean layout with easy soldering access and so on.
I want to get this rebuilt before turning on. get the ancient capacitors out [only being very complex resistors at this age I suspect], and get the various resistors checked and changed as per. My view is to aim for reliability in the choice of replacement parts rather than slavish adherence to like for like NOS type parts. The very best modern sympathetically introduced for safety and reliability. I am not even interested in any effort to "improve" the sound quality. Just to equal what it was capable of back in the day.
I have not decided what to do precisely, and would appreciate any advice you might offer. At least it is not ruined by over-heating or cobbled repairs so far. Like a 61 year old virgin really!
ATB from George