depends on if you are using a grinder and sawzaw or a plasma cutter. If you have a lift or if you are doing it in the driveway.
If you have never done one...i would say a couple of long days (3-4), just to be honest. Depending on how you work it could be longer. Once you have done one or two...you can knock it out pretty quick. But there is always the learing curve. Anyone of the DIY kits are farly easy...they are all the same.
There are about a dozen different manfactures for the kits....just pick the one you like.
(the cheapest isnt always the best)
Seth