I have a 79 CJ5 thats in real good shape and was thinking about repowering with a 4.3 EFI gas burner and then a buddy showed me a youtube video of a 4bt in a jeep rock crawler. It was love at first sight. I own a charter boat with a pair of 6bt's and needless to say I am very familiar with them. I am posting this get some advice on how to get started. The Jeep has the T-15 tranny.Will that bolt up? What do I look for in a motor? How much welding is involved? How expensive is it after the motor purchase? Do i need to regear? Any advice is appreciated. All I really want to do with the Jeep is a run around truck. No interstate, just a 55mph is just fine. The Jeep is geared with 3.07 right now. Is that too high?