I have done it several times. Get an engine support bar from harbor freight. Support the motor from the top. I have gotten that transmission bracket off with motor in but you dont need to remove the brackets to get to it just part of one. Its easy and straight forward. Drop cross member and move suspension out of the way. Make sure you PULL OUT THE DIPSTICK before you reinstall the oil pan. First time I ever did this I sandwiched the dipstick in between block and pan by not removing it when reinstalling. Clean the mating surfaces really well, use Nissan seals, and black permatex for gasketing. Dont waste time pulling the engine unless there is a lot of other small leaks that need to be taken care of. Took me 3hrs to uninstall and reinstall on my back in a driveway, but im a professional tech and know the car well.