Disc brake conversion (70 Dart)

Also just picked up on this. Have to agree with #37 and #38 - very profound and sensible. Also, the 'tongue-in-cheek' reference to Willwood in #42.
I also agree that most drum brakes (not 'breaks'!) are well capable of squealing the tires (f or r) - but, biggest factor here would be power assist. My Signet has the 9-inch drums. Stock 13 inch tires were quite easy to 'squeal', however, I find myself adding left foot to the right foot for quicker stops (poor man's power-assist).
A booster has to make a difference, but I may not go that route. Perhaps too much 'playing around'?
Since this car will stay with the small bolt pattern, likely the (four-piston) set-up (from '70 Swinger) will be utilized. That will also include the booster - and new rotors. The Dart will go with OEM setup as donated from '74 Duster, but with new rotors and calipers. Another benefit is the larger studs / bolt circle - which makes wheel selection much easier. However, aftermarket rear axles will be needed - at a significant cost. But, I do have access to 6 good spindles and 4 brackets and, upper control arms as well, because the ball-joint stud is bigger (same as B or E-bodies). The rest is little stuff and low in cost.
To some people, installing 'aftermarket' brake system would be almost like putting Chevy small-block under the hood. (yikes!) Most of us would prefer to keep as original as possible (ie: numbers-matching) for any Mopar with 'H'-code engine (or higher). But there are always safety upgrades to consider - at a decent cost - and I for one don't need to brag about 'parts-unknown'.