I was checking around the local site here in Utah and found a used 2004 4R70W, the guy said it came out of a 2004 F150 4.2L. It does have 50k miles on it, it was j-modded but the accumulator springs are still in it. He said it comes with the TC also. He is asking $750 for it, is that a fair deal? I have no idea about transmissions. I do know I will have to swap my tail shaft in. Would I have to use my stock TC or can I use the 4.2L's TC?