When installing a manual transmission while the motor is in the car, it is hard to get the input shaft lined up straight into the pilot bushing while simultaneously engaging the clutch disc splines, and the throw out bearing over the input shaft bearing collar, not to mention all the mounting bolts, all while holding up an awkwardly shaped heavy-assed hunk of metal. Here is what I do- first I take an old output shaft yoke, insert it into the tail housing, and put the transmission in high gear which locks the input and output shafts as one. Now when you need to get the input shaft to align with the clutch disc, all you need to do is turn the yoke, and the input shaft will turn one-for-one. No need to twist the entire heavy transmission around. Then, I take two long 1/2" bolts with their heads cut off and screw them into the two bottom transmission mounting holes of the bell housing. Now you have two pilot shafts in place to rest the transmission on and guide it right into where it needs to be. And if you are like me, laying on the ground or garage floor with the car on blocks, don't risk breaking a rib. Place a 1'x2' piece of plywood on your chest so if the transmission slips, you are protected. Hell, just resting the transmission on the wood rather than yourself is worth the price of admission. Be safe!