2005 dodge durango engine swap

im about to pull the 4.7 out of my durango since the headgasket blew. I could have paid someone $2000 to do the head gasket but i got a engine with 51,000 miles on it for $1900. and being that I have all the tools to do the swap, and its not my first swap, I decided to do it myself. the only thing I have left to do before I can pull it is talk the bolts out that hole the engine to the tranny. but for some reason my impact wont even take them off, im so close, haha, anyways im 16 and if i finish it up this weekend it will have taken me a total of 3 weekends to do the job since I cant work on it after school because it pretty much gets dark right away. wish me good luck, and if anyone has ran into that problem with the bolts being practically welded on let me know how you got them off.
Happy Thanksgiving!