yes, you could just increase that series R before the network to match the sensitivity, and it might work well enough.
Ideally, though, you should rework the whole network. The T90 has a 5 db hump in its response abound 2KHz. The curves on the design you've linked to seem to have its high pass corner desiged to eliminate that hump. You may find that the T120's smoother response seems a bit low between 2-4 KHz with that filter. The T120 seems like a better choice for a ~2500 Hz XO, given the high resonance of the T90.
But, if you don't have the equipment and inclination to optimize the crossover I'd suggest just building the design as is with the T90. Lots of people seem to like the T90. I've never heard them, but I love the T120 in a similar system using the Focal 6W4254.