bootstrapping from a USB stick

[D. Hugh Redelmeier]

I have an oldish PC that only understands booting from 512-byte
sectors and then only with MBR disks.

I want to install large new disks on it, and no old disks.  These
don't even pretend to do 512-byte sectors: 4k all the way (3T and 4T sizes
aren't good for MBR either).

I was thinking that I should be able to use a USB flash memory stick
as the boot device, loading GRUB from there, and then having it boot
the OS from a big GPT hard disk.  The stick would be permanently
plugged in.

Is there any reason that this might not work?  Is there a better way?

Are there special GRUB modules that I need to convince GRUB's
installer to put on the USB stick?

What filesystem type is best for the USB stick?  My guess: ext4 is
fine.