Lol, it will probably end up bein everything, one piece at a time LOLOL. My immediate goal is to have something solid over the winter, so the 08 gx470 doesnt have to get road salt, or to have as a backup vehicle for my daughter if the 450 engine decides its reached its expiration date.
Look at your baselining in subsystems:
Mine had a dead/weak battery, so it needed a batt. Alt was putting out normal voltage
Fluids (just had an oil change, found the receipt in the truck, and the oil looked clean, so its staying for a while).
Trans drain and refill takes about 4-5 qts. Next time, I'll drop the pan and clean/replace the screen/filter. I'll do a trans drain/refill for the next few oil changes, and exchange almost all of the fluid. Dont do a power flush...bad stuff happens.
Knuckles and ujoints get greased. Check the knuckles with a white tie wrap to measure the amount of grease in the knuckle. I need to drop the shafts and clean/reassemble the slip yokes. Dont pump too much grease in the slip yolks, you can do damage.
Gear oil in diffs and tcase. No need for synthetic in the diffs, you can use that in the tcase. Ideally, youll extend the breathers at this time to up under the hood (i havent done that yet).
Cooling system: If youre gonna flush, you might as well do all the hoses (big and little), rad cap, tstat and gasket. Breeze clamps are a bit spendy, but are nice. Almost all of the small hose clamps are one time use deals, youll destroy them removing them. Clean the fins of the rad with a chemical cleaner. Use hose pressure, not a pressure washer for that, or youre going to have a bunch of bent fins or worse.
Still to do:
Scuff and paint rear bumper and trim pieces with Duplicolor bedliner spray. May do that tomorrow.
Remove factory roof rack, seal with bedliner spray. Its not leaking, so this is a down the road thing. Would be nice to take advantage of another good weather day for that.
Brakes: Need to take the tires off and look at the pads. No grinding while braking, no warpage in the rotors, but the pedal is soft. I need to flush and bleed. I'll inspect when doin the next step below.
Springs and shocks: Have a set of OME stock height lift springs, and tokico OEM shocks from my other truck that will go in this. rear springs are very soft, and I think the right rear shock is dead.
Tune up: Dist cap/rotor, plugs and maybe wires. These look fairly new, and the truck runs well, so thats on the backburner.
Tires: Still have to put some flavor of tires on it. Still trying to figure out what to run in 285/75/16, and have to clean off the remnants of an illfated plastidip attempt by the PO's son.
Oil pump gasket/screws, front crank seal, and belt pulleys. Have an alt belt pulley coming, and swapped in my old one off my 450. I'll prob do the ac clutch bearing at that time.
Oil level sensor/connector. PO's not too smart son or the mechanic damaged the connector(hopefully), and/or the oil level sensor. so the oil light stays on. I need to get under there and see if it can be repaired, or whats gotta happen to replace that. Oil pressure is good, and oil level is good. I'd prefer to fix it, rather than pull the bulb in the dash LOLOL, but its not a big rush.
Optional goodies/down the road stuff:
CDL/Pin 7 mod: I have an extra hazard switch, so this is going to happen soon. Since I have to pull the trim piece around the radio, I may throw in a bluetooth adapter to the pioneer head unit to get rid of the aux cable. I also need to fix the 12 volt plug, it comes out of the mount. Also need to see if they disconnected the broken power antenna when they broke the mast, and if its salvageable. If not, I need to figure out an antenna option.
HIR headlight bulbs up front. Had em in the 450 for about 10 years, worth every penny. Philips bulbs are the real deal there.
Airlift rear air bags. Have em in the 450, helps when i put 10 lbs in a 5lb bag.
Rear axle rebuild: bearings, drop the third member out, and install a spartan locker and new pinon bearing and seals. Since this wont be a daily driver, I can handle the mechanical locker clicking on turns
Front axle rebuild: Birfs arent clicking (surprisingly), so I'll run it until i see the soup, or feel enough play to warrant a teardown. Would entertain a front locker at that point, but havent looked at the options. Thats a ways down the road.
). Couldnt get to the two in the very back tucked way under the heater control valve. Had to substitute/modify a Carquest/Advance Auto parts B87310 hose to go from the T fitting down to the firewall. Its slightly smaller than the 5/8 hose. Everything took a touch of Dawn soap to help slide on, and was still a beeeyotch. 
