Car Number Positions for GP 1.13.

Hello...
I´m trying to use a 2005 carset, I think that it´s the only one available, but don´t have the position for the numbers on the cars.
I using GP3 Edit.
I downloaded the cars maded by CHouguin, but they only come as bitmaps.
There´s a way of put the correct positions for the numbers in the cars? They all have both numbers, but I have no idea how to put in the correct positions.
There´s a way? or I have to keep trying until find the better place?
Sorry about the english.
Thanks for some help....

you can adjust the Numbers with GP3 Editor on the right Hand where you can see the Car bmp´s. You can setting every Number for each car by yourself in this way

You can use MS Paint to set those numbers quicly and without making mistakes.
Or then wait a few weeks for my 2005 carset

SuperSonic, good news...
Already looking foward...
Good luck.
Trouble to use GP3Edit is to find the correct coordinates for the numbers, so, as far I know, is about trying until find the correct position.
I´m looking for a easier way to do this.

You can see the coordinates in the status bar of the Paint program.
But note that you have to subtract 128 of the Y coordinate of the top textures and 256 of the right side of the car.