I had a CEL for #3 misfire. pulled the plug and it had oil and the smell of coolant. Plus I have steam from my tailpipe now.

I've done a lot of work on 22REs but nothing really on a 5VZ.

What should I look for? Are the heads usually faulty like the 3.0s? Any tips would be great.

 

I did my 3.4 HG a few years ago. Horrible job, no....labor intensive, yes. Get your hands on a copy of the FSM.

Likely the heads will be ok if you did not let it get way hot and boil over. Once the heads are off take them into a machine for pressure testing. If they pass testing and additional inspection by machine shop, then have new valve stem seals put in and the heads resurfaced.

I used the Toyota Engine Valve Guide Gasket kit and a new timing belt kit including water pump from ebay seller AirCabinMan.

Take a look here for the process:
http://www.ultimateyota.com/showthre...ght=overheated

 

I've only taken the heads off, but it wasn't too difficult. You'll need to pull the intake, upper and lower plennums, intake manifold, valve covers, cams (making sure to use a 6x1.0x20mm service bolt in each of the exhaust cams); that's just to get to the head bolts. You'll also basically need to do a full timing belt job, since you need to remove the belt from the cam pulleys in order to remove the cams.

A heads up on the head bolts, FOLLOW THE FSM, they're tight, really tight. I ended up sliding a 3' jack handle over a 15" breaker bar to get the bolts loose. Go slow, follow the pattern in the FSM, and turn each bolt a little bit at a time; mine all let out a loud "POP" as they began loosening, so I would turn each one POP at a time (the idea is that you want to keep as unform a pressure on the head as you can, so by loosening them all a little you keep them all about the same torque loading).

Once they're out, take them to a machine shop for hot tanking, inspection and a valve job. Be on the lookout for cracks in the head between the valves. Here are some examples of such cracks (and also why I didn't finish the HG job, but bought a new motor, was for a 3.4 swap and didn't want to risk it):
https://www.yotatech.com/forums/f160.../#post51943873

Good luck with it.

 

When you decide to do this and want some extra help if it is over the weekend your only a few hours away.

Any extra tools you might need

Let me know.