transferring boot

[Eben King <eben@gmx.us>]

I recently got some SSDs, and decided to use one of them (a 256G model) 
to boot from.  I want the change to be undetectable, in that from a user 
perspective, nothing seems different, just faster.

I currently have a 2T HD, partitioned with GPT but booting by MBR.  Yes, 
that's probably weird.  When I installed Debian I was unaware that the 
installer would only install grub to boot using the method that the 
installer booted.  My BIOS/firmware will boot using either method, but 
defaults to MBR if both methods work.  You can force it to use UEFI on a 
one-time basis.  I want the SSD to boot using UEFI.  Is that possible, 
and if so, what's the best method to go about it?

My ideas are:
1. dd / onto the SSD, then modify it to boot UEFI.  This sounds hard.
2. Install Debian (the same version I run) onto the SSD, then modify
   /etc and whatever else so stuff works.  This sounds error-prone.
3. Wait until I upgrade to Trixie, then let the installer hash it out.