After shrinking a number that looks like this 1.76082312808723 down to 1.761
by formatting to 3 decimal places, I need to add a [b] on the end but it
bounced back to 1.76082312808723[b].
What do I need to do to the cell so it looks like 1.761[b] or something very
very close?

I have a huge list of numbers and I'm going to have to replace the "b" in
pretty much every number with an "a"or a "c" on most numbers.