Hold the cut section up to the first donor object. Use a dry erase marker to trace a section equivalent in size and shape (Image 1). Cut this part slightly larger than the traced lines, leaving room to work with when fitting the pieces.
Next, fit the donor piece onto your pumpkin. It’ll take some finessing to get the piece to fit just right so carve thin layers away from the donor piece until it fits (Image 2). Once you have a good seam, put this piece aside to be attached later.
You want your pumpkin to look like it’s been put together from various parts, but these pieces can come from the same pumpkin. A great way to cheat is by cutting your pumpkin in half and stitching it back together. When you cut the pumpkin in half, draw lines in the opposite direction (Image 3) as a reference to remind you how these pieces fit back together.