Doing one service on Holy Thursday? I’ve had that restriction for several years. What I have done is splice the two together. Here’s an outline:
Maundy Thursday Call to Worship
MT hymn like “In an Upper Room Did Our Lord Prepare”
MT Call to, Prayer of Confession and Assurance of Pardon
Then start into the Good Friday Tenebrae service with the SHADOW OF BETRAYAL portion and follow to the end. Usually I cut down on the music and put some readings one after the other to help on time.
I hope this helps! I’ve found it to be a decent substitute when the congregation says it will only come to one service.