There have been a lot of really incredible custom versions of jet Optimus, but most of them end up destroying Jetfire in the process. I enjoyed the toy, and he was one of the things I liked the most in Revenge of the Fallen, so I thought I would see what I could do to improve the combined form while retaining the ability to transform Jetfire and Prime independently. I decided I was OK with partsforming for the combined form, as long as I could transform him normally to jet and robot models. The actual modifications are relatively simple, fairly reversible, and in my opinion make him better in the end. I pulled the two long pins that the two side pieces of his big gun fold on, separating it into three parts. For Jetfire's Jet and robot mode you can push the parts back together, and clip them onto the two clips on his back normally, and they will hold the center gun in place. I also trimmed the clip that connects Jetfire to Prime's waist to let Prime's hips move further. On Jetfire's back is a large panel that makes the body of the jet between the engines and above the big gun. lift it up, and on the bottom are two plus shaped pegs with a round hole in them for the legs to peg into in jet mode. I trimmed off about 3 millimeters of the cross shaped bits leaving the center ring shape intact. This keeps inside strong enough to hold the peg for jet mode, and lets you use the outside of it as a round peg to attach the side panels of the big gun to. This makes them look like the two wings jet Optimus has on his back. The last modification I did was to cut slots halfway through the blue hinge part that holds the nose of the jet in place on Jetfire's arm. This let me pull those parts off of the pins to combine, and snap them back in place when I am done. Once the modifications are done, you start to combine Optimus and Jetfire. From Robot mode, remove the cane, machine gun, the three parts of the big gun, and the two front nose sections and set them aside. Transform Jetfire's body normally for the combination, and connect the two shoulder clips and the clip on the pelvis. take the two panels from the side of the big gun and using the round depression where the end of the cane handle would fit, peg them onto the bottom of the back piece of the jet forming the lower rear wings. Unhook the bottoms of Prime's feet, turn them upward, and rotate his ankles 180 degrees. Turn Jetfire's thighs down and his lower legs foreword, clipping the bottom of Prime's foot onto the clip in Jetfire's ankle. Fold the side panels of Prime's sleeper against Jetfire's body, and rotate the gas tanks foreword. Turn the smokestacks around and against the body as well. Jetfire's arms fold down in front of the upper wing and the lower arm around underneath the upper wing strut. Use the blue hinge piece on the nose to pinch the triangular shoulder bits on Prime's shoulder to hold them there. put the big gun upside down in his hand and the small one on his arm, and he is ready to start taking names and collecting faces. I would like to still find a way to take apart the upper wing/engine and make it transform into a more accurate shape, but I still haven't found a simple enough way to do it yet. Anyway I thought someone might enjoy this approach, so I thought I'd share.