Engine swap or just rebuild...

ok here'z the deal...i got a 1992 Grand Prix LE with 89K mi on it...the engine'z knockin and it haz a lil whine or sumthin when i slow down, the whine really kicks up when the car downshifts into first gear...(its an automatic)...i waz thinkin, should i just rebuild the engine or should i replace it with a replacement 3.1L, or should i go for the 3.4L? how hard would that be? would i need to get a whole new tranny? i've already got a Ractive high flow air filter on it as well as a 3A racing DTM-style exhaust...at times the engine hesitates and yes, i've re-installed the MAS into the intake tubing, right next to the filter, so thats not a problem. What do you think??

Oh, and about the engine knock, i went and unplugged the front spark plugs one by one and with the first two, nothing happened...but with the third one, the one on the right, the knock got louder. My grandfather thinks that this could be a wrist pin for that piston...but my ex-boss says i just created a misfire...but thats not true because i just created a dead plug...if it created a misfire it would have done it for all the plugs i pulled...

i own a 1995 GTP and im thinking of doing an engine swap out of a 99 supercharged grand prix right now i have the 3.4 with a fresh rebuilt tranny warrantied for 2 years with tranny cooler and B&M shift kit that ill be willing to sell along with the wiring harness. the motors also got new top end gaskets intake, plenum and heads with 120K miles trust me its still quick i smoked a lexus ES300 yesturday comming from from grand forks ND. leave a reply and ill get back to you. make an offer im not sure what ill let it go for. the new 99 gtp motor should be here end of april.

im not sure...lemme think about wat i wanna do...i'll let u kno

Do what he's doing. L67/4t65eHD swap

ok, but how much would that cost?? i mean...im only 17...i dont got the money i would like...but i got some money...