Yes, but it will involve some work.
Go into the avionics.ini of the particular aircraft. Look for this entry:
Note the bolded text. This is the 'hole' that defines where everything visible in the HUD is seen...it's defined as 2 corners of a rectangle. The first number is left/right, the second is up/down. Increase the size of those numbers, that will increase how much of the screen the HUD takes up.
Now, look for this next section:
Note the bolded area...adjust this number to adjust the size of the text in the HUD.
Now, note the entries similiar to this
See the bolded areas. These numbers define where in the HUD space the TGA falls, and how big the TGA appears. You will have to play with each component to get the position and size right.
Good luck...you will need to do this with each model.
Of course, it could have been easier to simply fly around in 'zoomed out' mode, hitting the view key to be able to read the instruments...then zoom back out.
FC