24 drivers in the race

How I can change the 22 drivers in the race to 24 drivers? What file should I edit, please? I forgot it. Thank you very much...

There are two files to edit, actually.
First, open the config.exe file in the main folder and find this line:

GRIDSIZE=22

Change its number to the number of drivers you want in the race (24 in your case).
After that, go to your profile folder in the Save folder and open the .plr file with the name of your profile.

Ex: F1 Challenge 99-02\Save\Profile\Profile.plr

There, you will find something like this:

CURNT Opponents="21"
PRACT Opponents="21"
QUICK Opponents="21"
GPRIX Opponents="21"
CHAMP Opponents="21"

Change all numbers with the number of opponents you want (23 in your case).

Any problem, just tell me, I'll be glad to help

Oh yeah! That's it, what I woulda know! Thank you very much, Danny!

Edit: "Your" CONFIG.EXE is "my" CONFIG.INI.

Oh god, why???
Sorry, I wrote it way too fast and scrambled everything in my mind.
Good observation, though

Don't worry, Danny. My mind is faster than my writin' too. The idea is primary, not words.