i've done some technical research comparing "shorty" headers and "long-tube" headers. the information i've found indicates that long-tube headers produce more horsepower than shorty headers due to the flow characteristics of the long tubes which apparently "extract" exhaust gasses more efficiently and in a more "robust" manner. however, shorty headers are obviously easier to install and remove simply due to their design. if i were trying to design better "classic muscle car" Mopar headers, on the shorty headers, i would make the tubes as short as possible to a collection point and then i would design a series of "attachment" collectors that could be "swiveled" or "angled" depending upon the need of the car body and accessories. on long-tube headers, i would make them in two pieces where all four tubes were short and then the longer under chassis section slipped into the manifold section individual tubes like what you have with a standard exhaust pipe. i can't believe such a design would detract from the efficiency of the long-tube design. frankly, i think old mopar guys would be happy to pay between $500-1000 for either of these designs if their chief advantage was ease of installation and removal. i know i certainly would pay a little more money for a set of headers that could actually be "installed" or "removed" by a "normal" person.