Hi all - thanks for the help & support in identifying the issue with the spindle drive 👍🏻

I sent the drive to Sprint, who were super-helpful by the way, for investigation prior to repair or replacement.
It proved not cost effective to repair and the 1600i was recommended as the replacement.
A couple of hours making up a new mount (as it’s bigger than the 1200) and wiring in and we were in business!
No ‘rogue behaviour’ from the spindle on boot up and no tripping the power!

I’m still apprehensive about wiring into the mint board, in case that’s what killed the old 1200.
So I’ve wired in a 10k pot across #1 & #3 on the board.
This controls the spindle rpm, but I’ve still got an issue in that I don’t get full range.. by ‘educated guess’ (uncalibrated 😉) I reckon I’ve got 3krpm - 4krpm… but no lower.
I’ve played with the minimum and maximum rpm’s, but still stuck at the minute.
I’ll get in touch with Sprint, but anyone retrofitted a 1600 or 1600i spindle drive?

Thanks