Here is how i do it on my Avonds F-16.
A pushrod tube are glued from the chute housing to the front, where a servo does the cutting part of the job.
A UC wire (line controlled model wire) is stiff / thin enough to be pushed all the way to the front. the loop on this wire is simply thread over the servohorn.
When this servo rotates, the wire are loose.
It releases from inside the housing at the rear with a analogue miniservo after the original fullsize method. So I use two small servos on one switch. step one is deploy, the second is cut away.
A weaklink makes sure the chute will snap the line above 80 km/h.
I sew all my chutes myselves