in ssaow 1.3.4
under
void M00_GrantPowerup_Created::Created(GameObject *obj) {
there is a
if (Settings_ShowPlayerPurchase) {
char PurchaseMsg[512];
sprintf(PurchaseMsg,"%s purchased a %s",Get_Player_Name(obj),Translate_Preset(IsPlayerVehicle(obj)));
FDSMessage(PurchaseMsg,"_PURCHASE");
}
based on that in that function make something like
if (Translate_Preset(IsPlayerVehicle(obj)) == "Nod Flame Tank")
{
kill tank
grant flame thrower
}
else if (Translate_Preset(IsPlayerVehicle(obj)) == "GDI Medium Tank")
{
kill tank
grant rocket
}
you will find the tank names in the server2.ini