Materials:
Hot glue
E-tape
Any good ram rod (I used a very small dowel rod that I don't know the exact size of)
FBR/Caulk Saver
1/2" CPVC Piping
Tools:
Hot glue gun
Dremel (I use a 4000, any kind would work.)
Hack saw (could be replaced by dremel)
#0 Screw Driver
Flat head screw driver or something very hot.
Your hands (Prosthetic limbs will work as well)
Firstly, Here is your stock SM750:

As you can see, there is an orange cap at the front of the blaster and one near the back of the blaster by the pump shaft. I got the one on the front off by being very persistent with a flat head screw driver, but my glue seal was weak. You will most likely have to use some boiling water or a heat gun to get it off. And as for the back cap, I just broke the cap in half by using the force of prying the blaster open. Once you get through these problems, you'll find your internals which will look like this:

Firstly, I removed the pump shaft and plugged the pump by simply putting hot glue over the OPRV hole. Make sure the hot glue is either flush or below flush with the bump head so the glue doesn't mess with the check valve:

Sorry, that image is a bit blurry. Anyways, next cut here, where I'm pointing, with either a cutting wheel on the dremel or a hack saw. You'll know where to cut because there is a small groove there:

Now, it should look something like this:

Next, cut your CPVC barrel. Your going to want to do somewhere between 4-5 inches. Also, please note my barrel length in the pictures are about an inch too long. Don't be a noob like me. Then, after you cut it, wrap e-tape around it until it fits on the little snub of barrel left:

Next, use any sort of sanding bit on your dremel and hit up the front of the barrels with it for "Supa Smooth" re-loading. **This isn't required but recommended:
I accidentally lost the picture of the glued in barrel, but just simply hot glue the barrel into the snub on the tank. Now, remove the trigger spring and put hot glue over the spring by the pin that I don't know the technical name for (Pin spring, maybe?)
Once again, I'm sorry for the blurry image. But now, just fit everything back in the shell like so:

And now, screw it back together and it'll look like this:

Now you're done!... Or are you? *Dun Dun DUNN!* Well, I suppose you could stop there, but you are following this write up, aren't you? So now, cut a small piece of cpvc and a piece of FBR the same size:

Now, hot glue the piece of FBR in the cpvc then drill a hole, with the drill bit on the dremel of course, until your ram rod fits in the hole snugly:

And now, you are really done!... Or are you? No, you actually are:

Here it is in comparison to my modded new style SM750:

So yes, there is my first write up! *Hears cheers from the crowd*. This thing can punch a good 90-110 feet depending on the dart and would be a good blaster for pistol rounds. Like I said at the beginning, if you have any constructive criticism please leave it below!
Audios Amigos!
~~Link
**Sorry about a few of those pictures being extremely large... stupid image shack, messing up my pictures...