Hi there and welcome!
I'm with
sandyut
on this one. I prefer to the smoke the whole thing THEN also slice and vacuum seal then. Brisket seals and reheats amazingly.
If you really want to cut the approach I would take would be to do a very aggressive approach to how I trim my whole packers for cooking. I use the following image to explain how I recommend trimming away the thin portion of the flat. Do the same but move the green line way more aggressively towards the point muscle:
View attachment 463394
I say this because the flat muscle is the problem child and cooking together with the point helps keep the flat from drying out and makes for a better product.
The left over flat you can smoke or cook any way you like and you should have a pretty good amount (almost half the brisket).
In all you get a large chunk of just flat BUT you also get some flat point combo which is like the best of both your worlds :)
Here's my post on how I a trim a brisket where I pulled that pic from :)
Well I have had a number of private messages where people ask for more info about what I do when I trim away the thin Flat portion of a brisket I smoke. So today I figured I would just post about it with plenty of pics so it becomes easier to understand vs when I just go "blah blah blah trim...
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