what i do is get a rolling jack anduse the jack to lift it as you aim it into place.

I'd like to thank you guys for the info I'm having the same problem and found this on a google search.

I have an 88 Toyota Supra Turbo. I am trying to replace the transmission and I am having trouble getting at the nut above the starter(hopefully the last one). I can see the bolt but i have little to now room to move a wrench and a ratchet wont work either. Is there something else I need to remove before trying to take this nut off?

I've had to do this 3 times in a row over 2 days, then another time removing the transmission. My trick was to use a 14mm (or was it 17mm) box end on the nut just above the starter, and use a ratchet with a loooooooong extension to get to the bolt head on the transmission side from underneath. Still a PITA, but it worked.