UVB Help Needed..

[usafvet98]

Hey,
I have my 72 gallon tank which is 48" long but the uvb I have was for a 10 gallon 12" long tank. I understand thats not enough uvb so my question is: How much is too much UVB? I talked to Todd over at lightYour reptiles and I am sure I want the Arcadia T3+ but do I need the 46" to go the length of the tank? How would I mount it in the tank? Sorry for all the questions, I just want to make sure my little buddy gets the best care possible..

Thanks in Advance

Brian