If you want to work on the chassis while the cabinet is away being restored it may be worth considering making some sort of jig to support the tube so you can reconnect the chassis and support it to work on the reverse side.
Maybe something could be simply made using wood and / or Dexion shelving if you can find some old bits? These often turn up in house clearance auctions.
Take precautions with the tube though while it is out of the cabinet and not behind safety glass!
As well as the wax coated capacitors you may find some small brown Hunts branded capacitors. These are best removed by snipping the wire each end and carefully lifting them out. it is very easy to have one crumble into bits and then you have to consult the layout and parts list diagrams to identify its value. (Capacitance and working voltage)
Any chance of taking a photo of the underside of the chassis ?
If you take a methodical approach to this you will soon have it working again!
Rich