I changed mine with the engine in the sled. Can be done with alot of patience and a little bit of persistance.
Steps I followed:
1. Ordered the bolt from poo just to ensure that I didn't have any compatability issues
2. Removed the secondary clutch, chassis stiffener and the fuel filter (all on the PTO Side).
3. used mirror to locate the bolt hole. It is exactly where indicated above but having a visual just makes it real.
4. Tied a piece of string to the bolt so that if/when dropped it's easy to fish out.
5. put bolt through DET sensor
6. Tried, tried, tried again and again and again and again.... and again to get the bolt into the hole and started. After some time, I managed to get it.
7. Used a 1/4 inch ratchet to tighten/torque the bolt.
Notes:
1. removing the gas tank doesn't buy you any room....
2. tried to get my 9 year old son to help but wasn't up to the task. IF you have or know someone mechanically adept with small hands, the task would probably be much easier.
Good luck! It can definitely be done!