Upgrading
 

i have a 2.9 v6 and it has 190000 on it how can i update it while keeping my cost down. aka adding hp and extending the life of it?

at that mileage horsepower adders are not typically advisable. Could it be done yes but at 190k I'm sure there is a lot of wear on the internals and adding extra stress may shorten its life if anything. Your best bet would be to save up for good used motor or a rebuilt. And if you want more power id personally save up for a swap you have a good candidate for a 5.0 and your well past emissions inspection so you could go all out.

what would a ball park be for a 5.0?

depends on what you want and what is available in your area I've seen 5.0 expos go for 2500-3500 and they are best since you can pull pretty much everything you need for them and then part out whats left after. If you plan to build it up then the price will be whatever you decide to add as far as performance (cam upgrades etc.). But seeing as last i looked a rebuilt short block goes in the neighborhood of $1900 (not including any parts that aren't reusable from your old motor) The 5.0 is a solid option for the price and you'd probably double your power capability. Also if you go the expo route you can get a lower mileage trans to go with it (fem the expo) which will save some money there to. But you can just buy a 5.0 used low mileage and go that route.

Least expensive would be to use a carb and distributor V8 so no computer or sensors, although emissions testing can be an issue.

And V6 transmission might not hold up well with V8 power, so.........
Then you need trans AND transfer case with driveline changes if 4x4

He should be ok on emissions its over 25 years old which is the standard cutoff in the states.