data port change quantity and cost per item proplem

I have item has wrong in quantity and cost and unit of measure so that i create new item with same name then block old

then add new entries after correction .I decided to make data port export all entries to specified item to text file then change it and import again  from tables item ,value entry,item ledger entry which fields will change in this.

before changes

quantity    invoiced quantity   remaining quantity  unit measure

2.5           2.5                              2.5                                ton

value entry

cost per unit  635

i need after changes 2500  2500  2500      kg

cost per unit  0.635 

My question after changes  which fields i will change

are this only and when i change change purchase entry only

please help me if possible

thanks