If you're used to %LT, get the HR monitor. It'll help a lot.

And as a little guy (weightwise, anyway) the hills may be your friend. Think about road racing as well as time-trialling.

The big difference between racing and TTs is that threshold power is no longer the principal determinant. What kills racers is the repeated surges, banging up to VO2max and then having to recover at speed before the next surge comes along. Bear that in mind when you're thinking about training regimens.