One of the most important things is FLUSH the cooler and lines out so the new lvl 2 will work good from the start. Hot trans fluid works the best. Some shops have a Hot Flush machine. This machine preheats the atf so the cleaning agents start working. Kooler Flush will work OK. If you have a stall converter, you may need less than 12 quarts of atf. Remove the O2 sensors if they are close so you don't break them removing and installing the trans. Put a quart of atf in the torque converter and let it sit for about 3-5 minutes so the atf gets into the turbine and stator fins and you should be able to install the converter into the trans without spilling the atf. Getting the lines off is a pain. Un bolt them from the case without bending the lines. Remove the trans from the car then remove the clips and then bolt the fittings back in. The new trans should have new fittings installed. Put a little Vaseline on the o-rings and the lines will snap right in, if they are not bent. Then push the plastic dust covers back on. Double check all connections, nuts and bolts, etc. Use dialectric grease on ALL electrical connections. Put 4-5 quarts of your favorite atf in start the car and put it in reverse, (on jack stands, of course). This will circulate the fluid quickly. Fill to full, start checking stick at 9-10 quarts. When full, run through the gears making sure evrything is working. Put on the ground and check for leaks. Road test easy making sure everything feels good. After some heat cycles, you should be able to play a little. I usually have my customers watch for a couple of weeks for leaks and function before all out racing. Hope this helps.