Edit id3v1 & id3v2 tags with some different info in each

Hi there,
I want to be able to edit and view id3v1 & id3v2.3 tags on an my mp3s. On a basic tagging level I require the Genre field and the Comment field to be different but the rest of the information (Title, Artist, Album & Year) to be the same.

I have been able to edit the id3v1 tags by amending the option in Tools>Options>Tags>Mpeg section but on certain occasions when I switch between the tags and change things the ID3v1 tags will mirror the ID3v2.3 tags and therefore have just a partial comment due to the character restrictions.

Is there a way to view and edit both id3v1 and id3v2.3 tags side by side bearing in mind there are only two fields I require to be different? Or is there any settings or steps I've missed when switching between tags that would stop the information loss?

Many thanks

In Tools>Options>Tags>Mpeg have ID3v1 checked under both read and write when you're editing ID3v1 tags and don't have either ID3v2 box checked.

Likewise have ID3v2 checked under both read and write when you're editing ID3v2 tags and don't have either ID3v1 box checked.

Also when you change settings, refresh the view to make sure you're looking at the right tags.

Never have both ID3v1 and ID3v2 boxes checked at the same time.

Out of curiosity why do you want to do it that way?

It is a misunderstanding to think that MP3tag knows the contents of both tag versions.
All tag fields are mapped to MP3tag internal representations.
While reading, the priorities are like this: APE>V2>V1.
So you only see the contents of the tag version with the highest priority and cannot see the contents of different versions "side by side".
As soon as you write there is only one source for a field left - that is the mp3tag internal representation. And this means that you only write a single piece of information and not different ones.
All other attempts will probably lead to information loss, as you have found out.