Re: "Do not try this yourself."
I thought I'd trained myself to expect the unexpected, so you just KNOW how this tale will turn out: A customer in Inverness was having a server shipped in from a US supplier for a DR test; I checked with the customer and supplier exactly what they had provided, then headed north with spare 4-gangs, OS CDs, monitor, power leads etc. etc. I'd been misled before.
Arriving on site, for once everything I needed was there! Enough power sockets, UK power leads, UK keyboard, colour-coded cables & labels so it was obvious how to connect everything. Instructions from the supplier. And a "tested" certificate & config sheet stuck onto the server, signed by the suppliers engineer who had set it up. These guys really knew how to take the stress out of DR.
I connected everything up, hit the power button and heard the "Bang!". Yep, the server had been tested all right...on a 110V supply And then someone else at the warehouse had packed it up with UK power leads. Not really my fault, but I was kicking myself for not checking.
Rang the supplier, prepared to grovel, but they were very apologetic; Checking the voltage selector was on their internal checklists, so not on the checklist they sent to the client. They could get a new PSU to me within 24 hours, but couldn't get an engineer for 3 days. No problem says I, I've always got my Torx screwdrivers with me, how hard can it be? So you just KNOW how this tale will turn out...
Actually, you're wrong this time. It was straightforward, though more complicated than changing a PCs PSU, and I even remembered to change the voltage selector this time. And the rest of the job was silky-smooth.
TL;DR Trust, but verify