Home assistant blue and SSD (boot)

I have a home assistant blue still running on an eMMC. I wolud like to migrate to an ssd. It is easy just to move the data disk and keep the eMMC for boot. It seems very much more compiclated to boot from the SSD and I do havn’t found any step by step instruction to do so. As the need to reboot is at most a once in a month event, what is the advantage to take the trouble to boot from the SSD? Does anyone have a simple step by step instruction in that case?