A co-worker of mine is cranking his '68 Mustang Squareback to 11, he's yanking out the 500hp supercharged 306/C4 combo in favor of a twin turbo 392/TH400 (shooting for 1,000 hp) and converting the front suspension to struts and the rear to a 4-link. He's already sold his old engine and stock suspension and asked me if I wanted to buy the C4 for my Mark VII to turn it into a bracket racer.
The C4 is built to withstand 700 hp, reverse manual valve body, this input shaft, that output shaft, unobtanium clutches, yadda, yadda and it has only two summers on it which equates to a few cruises, some street races and about a dozen or so passes down the strip. He also has two torque converters, a 2,200 stall and a 3,800 stall along with a big external cooler. $2,000 is the price with the 3,800 stall, $1,500 with the 2,200. Obviously the 3,800 is way too loose for my car so $1,500 would be the theoretical cost.
I briefly envisioned myself slapping my way through the gears with a ratchet shifter, good fun. 
Then I thought, hell, I could snag a 4R70W and install a reverse manual valve body and wire up a switch for the converter lockup and be well under $1,500. Then I would have a deeper 1st gear and a .7 overdrive. This is where I took the red pill.
First: Overdrive. Wire up a speed sensitive switch for overdrive or just use a toggle? A toggle would be a pain...I suppose I could have the system default to allow overdrive and need the switch only to lock it out of overdrive, like the O.E. Ford system. Should be easy enough I guess... 
Second: Converter lockup. I could use a toggle to "arm" a momentary switch, like a push button starter, and then use that to engage lockup. But then what about unlocking?... I would like to be able to wire in an unlock switch to the brake pedal so that, if I tap the brake, the converter unlocks.
Of course the C4 is about 1 3/8" shorter than my Lincoln's AOD. If I were to use that I could buy a QA-1 K-member that has two slots for the engine mounts, one in the stock location and one that is 1" rearward of stock (that only leaves a net slip yoke difference of 3/8", should be live-able, right? 
). Better weight distribution! The QA-1 also moves the front wheels 2" forward. Positive caster and even better weight distribution! Then I would need coil overs or SN95 A-arms, spindles, struts and coil springs. Then I may as well yank the smog pump, delete the a/c, slap on some underdrive pulleys and put the battery in the trunk. More better distributionz!
Then I could BLAZE down the quarter mile in 16 seconds or more! 
And then subframe connectors, anti-squat brackets, c-clip eliminators, 31 spline axles, a spool, slicks, exploder heads and intakes, a turbo, megasquirt and... it would suck driving that thing to work.
Anyway, any thoughts on the wiring stuff?
