Chassis discovered at Yimkin works in 1963

After 50 years in hibernation and some speculation over provenance it's now safe to say that the chassis featured in this blog is without question a Yimkin. The discovery of a series of Kodak slides from the 1960's reveal that not only is this a Yimkin chassis but that it was the stable mate of XYN160 and sat beside it on trestle tables from 1961 to 1963. So a huge thank you to everyone who has generously shared information. So, what is the story behind this chassis?

Is this one of the 6 Yimkin chassis that has been canibalised... it seems very unliekly this could happen as early as 1961?

Is this a 7th Yimkin chasiss that was never completed and was later canibalised to create the chassis as it stands today?

Please take a look at the photos and let me know what you think...