I've been installing in stages, when I've had time and money. First I got my ANT751 and two TVs hooked up. Then I bought and installed the distribution amp and power inserter, added a third TV and hooked up the coax for a fourth. There were a couple of channels that we wanted that were only coming in sporadically (KOFY and MeTV) so I adjusted my antenna aim a little today and was able pull those stations and not screw up the other ones I had. The last step will be to add the fourth TV when I buy another converter box. For less than two months cost of cable we are now receiving an excellent selection of 36 channels in English and Spanish (we're a bilingual household). If one of us learns Chinese or Vietnamese we'll get another dozen or so.
Thanks to all who replied for your help and thanks for a great and informative website!