Andrew, yes make up the controllers but I suggest you spend some money on good robust heater straps. Many people prefer Dew-Not straps:
http://www.cloudynights.com/page/art...ter-straps-r22
http://www.dew-not.com/dew-not-desc-01.htm
They turn up occasionally for sale here but you have to be ready to pounce since they are popular
For the secondary, you really should do it properly with one of these:
https://www.astrosystems.biz/dewgrd.htm
But that takes a bit of work and depending on how your secondary mirror is mounted, might be a challenge to install. But they are superb at keeping dew off the secondary.
By the way, here is my experience of combatting dew:
http://www.iceinspace.com.au/forum/showthread.php?t=35705
http://www.iceinspace.com.au/forum/showthread.php?t=33207
http://www.iceinspace.com.au/forum/showthread.php?t=33500
http://www.iceinspace.com.au/forum/s...ad.php?t=31846