Splicing together 5-7 mins of classical string quartet music

I am a violinist in an amateur string quartet who would like to splice together 5 -8 mins of music taken from sections of the following well known light classical pieces for a friend's birthday:
Gabriel's Oboe
Mozart Ave Verum
Handel Zadok the Priest
Puccini O'mio Babbino Caro
Borodin 2nd string quartet 1st movement

I have all the digital parts for the full score and the individual quartet parts, they are all in D major and what I need is for sections of these pieces cut and pasted together so that the whole piece works well put together. The output would be a digital copy of the full score (all the sections put together as a whole piece that I can print off and give as a present) and also individual quartet parts so that we can play it. The final output must be sheet music that looks like it was written as an entire piece. I have uploaded some of the pieces (I can only upload 3 of them in PPH). We would probably need a couple of conversations just to agree the sections but that won't take long as I know the pieces very well.

I am looking forward to working with you!