This procedure is very easy, but risky.. so create an copy of gta3.img
Here's what you need to do.
Open up .exe file (the first one)
Locate gta3.img (Open a file)
And just drag all mods in Sparky tool (in what is gta3.img file opened.)
Ya'll shall be happy with it.
Hope it was usefull
If you liked it, gimme a