3787 is a great choice for a Tripel. it is my favorite. Wonderful flavor.
The key is controling fermentation temp. I like to pitch in the mid 60's , hold it there for a day or two until things get going. Then slowly ramp up the temp to the mid 70's. Give it plenty of time to finish. 3787 can take a long time to get the last few points of attenuation. If you pitch to hot, it is easy for the yeast to get out of control and heat up too fast.
The reason I mention that, is the first time I did a tripel with that yeast, I thought it was done and bottled it after 4 weeks. It obviously was not done and I ended up with really overcarbed beer. Not quite bottle bombs but close.
Give it plenty of time to finish. After you bottle it, set some aside to age.
Good luck with your brew.