The modifications only took about an hour and I didn't think to take any photos of the process. This is the Squirt PS4, which just became available this month, I think. It has 0.05" hex screws at each end of each scale, instead of rivets, so disassembly and meddling with parts is simple. The hex screws are threaded into a short stainless steel tube on each end on which the parts pivot. The width of the tool can be changed a little to accommodate addition of extra parts (this just results in the screws being incompletely screwed in). The scales are anodized aluminum, and everything else is stainless steel.
Putting serrations in the knife blade was simple with a small conical diamond bit and a dremel. Getting them evenly spaced was not difficult and they came out sharp.
I made the saw blade by cutting a sliver out of the fine-tooth blade of a Gerber Gator exchange-a-blade saw. To get the shape of the pivot end correct (so it would click open and closed nicely), I traced the outline of the pivot end of the screw driver part I removed. I then cut it out and shaped it with a dremel. The space it went into actually had two small screwdriver bits (one pivoting at each end), so I put a stainless steel washer, ground down to a small outside diameter, on the other end to act as a spacer.
The saw works well. As an experiment I cut through a wrist-thick hickory handle from an old pick axe (with some effort), and it easily cut a thumb-thick root in the yard.
I was considering adding a small hacksaw blade as well (there would be just enough room), but it wouldn't be stainless and I don't want to worry about rusting parts.
The pliers and scissors look sturdy and functional. I haven't extensively tested them, but these are standard leatherman parts and weren't modified, so a detailed review of them might be more appropriate for the Gear forum.