Alternate Engines?

[boxer_1]

About a month ago I bought a 1996 Chevy Lumina (sedan). The stock engine is a V6 3.1L (about 160 HP). When I bought it there was a 'tapping' noise coming from the engine which was loudest when the engine was cool (on start-up). I first thought that it was a lifter. However, after having a friend listen to it and after some discussion, we came to the conclusion that it is most likely the wrist pin/piston pin. I did some research on the 1996 Lumina's and found that these particular engines where manufactured with a little too much tolerance in the piston pin, which is probably the culprit of the tapping noise.

Usually, when the piston pin is tapping that loud, it has been my understanding that it is probably only a matter of time before the engine goes. I'm not sure if it is not such a strong indicator that the engine is on a quick downhill slide because the tapping is from excessive tolerance as opposed to wear or not .

Anyway, my question here is "What engines could I put in the '96 Lumina with minimal modifications besides the 3.1L that is now in it?"

The fact that I think the engine is going bad isn't the only reason I'm looking into alternative motors. Although the V6 3.1L has fair pick-up, I wouldn't mind having a little more power.

I believe that the more sporty model Lumina, as well as the Monte Carlo Z34, had an optional 3.4L dual-cam V6 that can deliver about 215 HP. Also, in 1998 I believe the Lumina switched to a 3.8-liter overhead-valve V6 that would put out about 200 HP. Would I be able to put one of these motors in the car without a lot of mechanical hassle with modifications?

Again, all I'm basically asking is "What options do I have for the '96 Lumina as far as replacement motors go?" I know some mechanics, but nothing that would qualify me as a mechanic of any level, especially when it comes to the newer vehicles. I would need to hire someone to assist me in any motor change which is why I'd like to know which ones I could look for used that could be mounted in the '96 Lumina without having to pay someone an arm and a leg to help me put it in because of modifications.

Thanks all for taking the time to read my post. I used to moderate a web design assistance forum, but of course this particular forum is new to me so I apologize in advance if I've posted this in the wrong forum or if the question is out of line with what is usually asked/discussed here. Thanks in advance for any help anyone can give me with this question.