The easy fix to just make a local driver would be to swap that 4 speed out to a 3 speed of the same vintage. The 3 speed would have 2nd, and 3rd gears synchronized. That would get you back to a stock six bolt axle torque tube if that is the direction you want to go. That unique master cylinder bracket should still fit. Once you start down the other path it will be a money pit in my opinion. If you drop in a v8 well then you will have to upgrade the brakes, then you will have to upgrade the steering, then you will have to upgrade the suspension, then the wiring, interior, 3 point seatbelts, door latches, etc... The list will be long, and possibly never get done. Which would be frustrating.
That 4 speed could be out of a 3/4 ton long bed pickup. I believe they had a 2 piece drive line with a carrier bearing.
Art
Hi Art,
That's the decision I'm trying to make, go as original as possible or modify it. I'm making a list of all the things I'll need to do the upgrade. As you said, suspension, frame boxing, wiring etc. There are several Mustang II packages that include the cross member, suspension, including disc brakes and steering. I was planning on getting a wiring harness anyway since what's in there now is just about 100' for red 14 gauge that runs everywhere. I'm just going to see what the bottom line is and go from there. I'm not going to be putting in some monster LS motor with 600 hp, I'm thinking something like a simple 327 with a Holley or I've just found a Fenton intake with 3 deuces that would look pretty cool under the hood.
Joe