Trying to FIX a Faulty 1979 & 2010 Big Trak purchased on eBay

Hi, this 'trying to fix' video shows 3 Big Trak (Bigtrak) toys purchased on ebay for spares or repair. 1 of the Bigtrak is the original one that was released in 1979 and the other 2 are the re-release model from 2010. I show the complete process in the video going from the unboxing to the final result and hopefully you will see my fault finding process and thinking behind it :-)
Remember that this is just for entertainment and I am not an expert in these repairs. The processes in the video may not be the best way, the correct way or the safest way to fix these things.
I do love fault finding and trying to fix broken things so I hope that comes across in this 'Trying to FIX' series.
Many thanks Vince.