i'd just go find a cheap/free 4k and chuck that in if its just your run around... or even give it a light re-build if you plan to keep it for a long time.

 

i changed my motor the other day. tied a rope around it slid pole through rope over top of both guards my mate on one side and me on the other put pole on shoulders then stood up and walked forwards. a 3rd person would deff be a bonus to guide it.

btw: i dropped box out first cause it so easy and can do that by hand on your own.

 

ps. if you take the head off first its alot easyier/lighter

You should be able to hire an engine hoist from somewhere for cheap anyway. You can pull an engine out and put one back in, in under 10 minutes, not including wiring etc, so hire one for the shortest amount of time possible, have all your old engines accesories disconnected before you get the engine hoist, then take it back before you connect the new engines accesories.