The two biggest challenges were planning what/how to cover and playing with the rest of the ensemble.
I spent a good amount of time contemplating what to cover. For those who have played the orchestral "Symphonic Dances," it's very similar in orchestration. I'm glad to have played that version numerous times. It covered most of the challenging parts. In order to fit in the space and cover as much of the part as possible, I decided to not use congas and only used two timpani. I doubled up on cymbals and bongos. Few of the accessory parts were covered by the drummer. I wrote A LOT of arrows and notes in the part. I found that setting up the toms 'marching quad' style reduced the amount of space and made the part easier to play. I put a set of timbalitos on the front end of the toms for the occasional timbale hits in "Mambo." For volume and control reasons, I used a LP Mini Shot. Since I was also mic'ed, all of the sounds cut through. Cowbells, triangle, finger cymbal and chimes are in the back part of the accessory set up.
Being at stage level made listening difficult. Most of what I heard was the cast. I was able to hear the orchestra when I was playing in quieter dynamics. A monitor set up under the vibes helped greatly, especially during "Cool." It kept me on my toes for all of the performances.
If you ever get a chance to play in a production of the musical, go for it! Just make sure to have some time to plan it out.
