Advice on recreating this part in Solidworks

I need to recreate this part in Solidworks and all the surfaces have to match exactly since the tool is already built. Couple of reasons for recreating the part is 1) to get as much modelling practice in Solidworks and 2) Since we are going to migrate all our parts to Solidworks form SDRC this is one part that will need some tool modifications. I have an idea how to do this (Using Convert Edges to create sketch edges) and extrude/boss or cut. I've eliminated all the radii from the part so I can use the edges at the base to convert and I will add the radii at the end. My main goal here is to have the part match exactly to the original so I'm assuming the best way to verify this is to do a volume check on both parts.

The way I normally would do it is to open the step file in solidworks and save it as a solidworks part file. Open a new part and insert the saved part into this new part. Use convert entities to create a sketch and extrude as a boss or cut. Like I said earlier the problem with my procedure is I have to keep deleting all the related entities created from the convert entities command and re-dimension the part (fully difined) so I can delete the original later.

All comments/suggestions are accepted.

Kris.

SolidworksParts And Features