Request for advice on converting a Colchester Master lathe for single phase supply

I have acquired a superb Colchester Master Mk 1 lathe and would appreciate any advice on setting it up in my home garage in the UK. Tony Griffiths (Lathes UK) has advised me to use a Siemens Sinamics G110 inverter to convert my 240v single phase supply to 230v 3-phase, and I have wired an appropriate Siemens 3 HP motor in the delta configuration. This combo runs smoothly and I am really impressed with the way I can control the RPM with a pot. Am I correct in thinking that I should not even bother to try the original starter switchgear, since it will almost certainly have a 415v coil, and I am better off using the ON/OFF digital control on the inverter, which will give me a nice ramp-up and ramp-down operation? I can't think of a neat way of retaining the existing switches, so I will probably replace them with a something along the lines of a plunger which closes a microswitch when pulled out but interrupts the 24v control circuit when pushed in, so it will behave just like the emergency switch during turnoff. I am not bothered about using the suds pump, which is the only other item requiring power, apart from lights.
Also does anyone have for sale a fixed or travelling steady for this lathe? I do a lot of optical work and will need to turn longish tubes.

Don't use the existing switchgear in any way shape or form, there should be nothing between an inverter and the motor.
If the machine's in a private home shop type setting there's no need for the interlocks and safety switches, which can be just one more thing to go wrong.

Light;- If it's low voltage, wire direct from a socket, bin the transformer and use the switch as normal, change the bulb for 240 volt.

Steadies regularly turn up on ebay, IIRC the mk 1 Master & Student are the same.