Don't both longram cars and shortram cars use the same booster/MC setup? The ram tubes are the same length, it's just the divider length in the castings that's different.
Either way, IMO a well-done disc conversion makes the cars safer to drive and shouldn't hurt collector value. but on a crossram car that's not a simple as a 'regular car'. It looks like the MC outputs to the output-thingy on the booster, and then splits out to all 4 wheels. How much of that system is repairable, except by specialty experts?
As for the booster, it looks like you could put any booster under the fenderwell that would fit, as long as it would mate to that output thingy that goes out to the brakes. I can't tell in this truncated picture if it gives you a dual-brake system like used in 67-newer. Regardless, the original probably won't have enough boost for discs for a heavy stop (that's the downfall of drum-brake boosters). The larger single-diaphragm booster that started in 71, if it will fit, is far cheaper than the 68-70 dual-diaphragm unit. Or you could look at any disc-brake booster that would fit to that output-thingy, and then plumb your rear brakes separetly out of a dual-section MC?
OR...
Were any Newports available with manual brakes in 63-64? If you're up to manual brakes, then you can have manual disc brakes, and it saves the headache of mounting the booster. You'd need whatever the factory used for manual drums (different pedal bracketry?) and then a MC from a mid-70s Dodge pickup with manual discs. I have this setup on my 68 Fury and I *love* it. Yes, the pedal is stiffer, but the long pedal travel makes things nice and controllable. And it stops VERY well.
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