Most snowmobile exhaust systems are held together with springs. The springs allow the the parts to move around with temperature changes and engine movement but always remain in tightly connected.
Removing and installing these springs is easy if you have the right tool. Here are two spring tools that I made. One of them is made from an old screwdriver that I ground two notches in the blade. One is for pulling and the other for pushing.
The second tool is made from the wire handle from a 5 gallon plastic bucket. The ell shaped bend on the end is originally from where the handle connected to the bucket. It is just the righ shape to grab the end of a spring. I put a piece of plastic fuel tubing over the wire to make a softer handle and then bent it into a loop. This is my favorite spring tool. It looks crude, but works great.