Is this on non-EE BG2 ?
If yes, then you just install the ToBEx and you will probably want to read the readme file... but essentially you just edit the .ini files with the options you want to enable. The readme explains this.
 
You don't exclusively just change kits, but the base rules, so every class and kit. Which is why the wspatck.2da shouldn't look like it does. But much rather it would be like this:

2DA V1.00   LEVEL1 2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 400    0    0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  1    0    0  0  0  0  0  -1 -1 -1 -1 -1 -1 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  12    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -23    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -24    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -25    1    1  1  1  1  1  -2 -2 -2 -2 -2 -2 2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2

 
The weapprof.2da file sets how many points you can place to the proficiencies for each kit ... and it can be edited so some kit gets higher amount of points to some proficiencies. Should it not be obvious, the -1 in the wspatck.2da file means 1 normal + 1/2 from profs. The 2 means: 1 normal + 1 from profs. And so on. There are a few other things that can effect this, like other equipment, and spell effects. Also the normal maximum is 5, unless the character is under either improved haste or a HLA effect where the max is 10, as it's the original doubled.

Great! I didn't know ToBEx has 2 ini files until u told me, and there's really a switch that can make wspatck.2da available to all classses. Thank u very much!

Is this on non-EE BG2 ?
If yes, then you just install the ToBEx and you will probably want to read the readme file... but essentially you just edit the .ini files with the options you want to enable. The readme explains this.
 
You don't exclusively just change kits, but the base rules, so every class and kit. Which is why the wspatck.2da shouldn't look like it does. But much rather it would be like this:

2DA V1.00   LEVEL1 2  3  4  5  6  7  8  9  10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 400    0    0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  1    0    0  0  0  0  0  -1 -1 -1 -1 -1 -1 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  12    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -23    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -24    -1   -1 -1 -1 -1 -1 1  1  1  1  1  1  -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -2 -25    1    1  1  1  1  1  -2 -2 -2 -2 -2 -2 2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2

 
The weapprof.2da file sets how many points you can place to the proficiencies for each kit ... and it can be edited so some kit gets higher amount of points to some proficiencies. Should it not be obvious, the -1 in the wspatck.2da file means 1 normal + 1/2 from profs. The 2 means: 1 normal + 1 from profs. And so on. There are a few other things that can effect this, like other equipment, and spell effects. Also the normal maximum is 5, unless the character is under either improved haste or a HLA effect where the max is 10, as it's the original doubled.

WoW thanx a lot~ I've never read the tobex doc, just setup following BWP script... I'll check if it works

It's "hard coded" in non-EE BG2... but you can install the ToBEx and make it "soft coded".
And it's not a "Fighter", it's "Warrior", which include Paladins and Rangers, as well as their the twos duals.
 
If I were to make a proper install of this, one should edit the wspatck.2da so that the first line would only contain zero's. Reason being that you shouldn't be able to make multiple hits with a weapon you have no training on. Even if you are a soldier of multiple wars.

Thanks! ToBEx changes many things... so how to deal with it if I want to change apr of non-warrior kits? All I did before is modifying the 2da or other files with DLTCEP...

It's well known that wspatck.2da contains the apr(attacks per round) of fighter classes, but it doesn't effect non-fighter classes. So is there a way to make non-fighter classes apr also increase with weapon proficiency? Is this in 2DA file or just hardcode? BTW, is this a standard AD&D rule, or just special in BG2?