Big boats need a bigger and more complex solution. For the H260 the cable tie thing is easy and cheap because the wires are small gage and the distance is fairly short. I did this 5 years ago on my H260 and I've never had any mast slap. There are other alternatives but this is the easiest. Remember, anything you put in the mast you might want to take out someday. Shoving foam or insulation up into the mast might be easy, getting it out might be a challenge.
Go to:
http://h260.com/vhf/vhf.html
Don't skimp on the cable ties. I used rivets on the cap and base. For salt water sailors special caution must be taken when using stainless screws/bolts on aluminum. Regardless how well machined the threads are, there are always microscopic spaces between the SS screw and the body. If salt water finds its way into these capillary spaces, an ideal galvanic cell is set up with resulting loss of aluminum in the area of the threads. Ultimately, the stainless srew is seized in the hole or worse, could fall out under load. Coating the threads with silicone sealant or grease before fastening will fill the capillary spaces around the threads and prevent intrusion of salt water. No seawater - no electrolyte, no corrosion. Got this info from the Boater's Illustrated Electrical Handbook by Charlie Wing:
http://www.amazon.com/Boatowners-Illustrated-Electrical-Handbook/dp/B001E50ORE
I've done this project twice, it's a simple solution to eliminate wire slap in the mast for small boats - larger boats with heavier cable, a different solution will be required.