As far as I can tell, you've understood the meaning of 'as large as life'.... but you've misunderstood how we use the word 'personally'. Starting with your actual question, 'as large as life' is used to indicate surprise at seeing someone 'in person' or 'in the flesh'. For example "I never thought I'd ever see him again. But I opened my door one morning, and there he was, as large as life!" As for the adverb 'personally', it doesn't mean 'in the flesh'. It's equivalent to 'myself' ( or yourself, herself etc) as opposed to another person. For example, if you say "Personally, I think it's a good idea", you mean that this is only your own opinion, and it may not be the opinion of other people. Or if you deal with something personally, you handle it yourself rather than asking another person to do it.

Larger than life is used when people have over the top behaviours or mannerisms. Example: Roy was always wearing flamboyant shirts which made him larger than life. It can also be used when making a small problem much larger than it is. Example: Steve was making the problem of a mole in his garden larger than life