OHH! this is going to be one sweet Toyota 4x4.
First off i would look at what kind of material of heads you will be looking at either Aluminum or Cast Iron. A lot of people think that Aluminum heads allow better air flow but that's not true. Aluminum heads are very prone to warping, cracking, galling, and reacting with fluids like coolants since Aluminum is a reactive metal, but you don't have to paint them to protect them from rusting and they take off and extra 40 pounds off the fount of your truck. Cart Iron Heads in this matter are way better for 4x4 since they are way more reliable then any Aluminum head. The only thing you need to do is paint them so they don't rust. I would paint them either with Engine paint Chevy Orange or high heat Black. I would recommend RHS Pro Action heads with 2.020 intake valve. Part No. 12317 These heads are not assembled but assembling heads is very simple it should only take about 30 min to one hour depending on how nice your valve spring compressor is. Make sure you get only Comp Valve springs, Valve stem seals, Lockers, Gide plates, 2.020 intake valves, and 1.600 exhaust valves. I once used a cheaper LORDCO brand stuff to assemble these same heads and nothing fit right so i had to return it all for Comp Cam stuff. This should run you up to about $1400 for everything.
For an Intake i would go with an Edelbrock Performer RPM Air Gap intake Part No. 7501. This allows the engine to really scream up to 6500rpms this will run you to about $220 for the intake. Or you can go with just a Performer Air-Gap Part No 2601 if you want to run at lower RPMs up to 5500rpm.
I have to go to work know but when i come back i will finish what i was telling you.
