I haven't seen anyone actually do a step-by-step, but I have seen many write-ups out there of how to do the swap. Really, it's straightforward. If you can remove the 7M on your own, there's no reason you can't stick a 1JZ back in it's place - the hard part after that is wiring, but if you can't work a crimper, Tommy will come back there and hit you on the head with a tack hammer, because you are a retard. [pardon the "Tommy Boy" joke there]
Seriously,
http://www.1jz-gte.us/ and
www.1JZGTE.com are good start points for info and/or links.