No bvi installed? Give this a spin:

home | blog | Terrible people and places | Covid-19 links | Teh Internet | guest blog |rants | placeholder | political | projects | Gwen and Liam | Citadel patched | Tools | Scouts

Good tip for showing hex from within vi. Thanks YorkshireKev!
In case that goes away, just stream with xxd to display hex:

Off again with:
:%!xxd -r

If you are more of a GUI fan, and want to install one without many dependencies, give Jeex a try:
P.S. Thanks Great site for tips and tools.