First, I would not use the DB8 or DB4E. These are UHF only and if you want to receive all available you need to have high VHF capability. I would use the Winegard HD 7698P antenna. This will be capability of receiving all but channel 5 NBC. You could use an all channel antenna (including the low VHF for channel 5), but this adds a lot of size and wind load and will only net channel 5 NBC. You should receive NBC on channel 45, a 2 edge at 171 magnetic. You will need an amplifier with a ton of gain. I recomend the new improved Channel Master 7777 with 30 db gain UHF and VHF. You will need a rotor. For your install use the Channel Master CM-9521A and 100 ft. of rotor cable CM-9554. If your garage has an even peak, I would mount on a 3' tripod CM-9003. All of theequipment is available at
www.solidsignals.com.
Starting at the antenna, Mount the amplifier as close to the antenna as possible. Run the coax and the rotor cable the best way possible into your basement or attic. Choose the best location to accomidate the cabling for your four sets and 110v power access.
If your cable run comes near your ground rod, use that to ground your coax (and mount if possible). In not you should drive a 6' ground rod at the cable entry point. You will need a ground block for your coax to accomidate the grounding task. The rotor cable should run directly from the rotor to the location of the rotor control box. With the coax in your basement or attic, the first device to be installed will be your amplifier power supply (part of your 7777 amp). This needs 110v power. After exiting the power supply you can mount a four way splitter that you can pick up at Lowes. From there you can run your coax to your set locations. keep your lines as short as practical. If your sets have ATSC tuners, hook them directly to the antenna. If they are analog you need converter boxes. Some DTV sets are a little tricky to scan when using multipul positions. Scan the area with the most channels. Hopefully your set has a channel add feature, or will allow you to direct enter the REAL CHANNEL as shown on Antenna Fools site. Converter boxes are usually have ADD SCAN feature to make scanning the multipul locations a little easier. You can come up with good beta rotor settings if you start your rotor at 0 degrees magnetic and use the Fool magnetic channel locations to aim towards the channels.