Stihl 034 super repair advice

Hi folks,
This is my first visit here and if it is like other forums I am a member of, it will be a great help.
The chainsaw is a Stihl 034 super
So today I was cutting a tree down for firewood when the saw chain brake suddenly engages in the middle of the backcut!:
I pull the saw free and find that the brake is jammed on and the handle won't release.
I cart it to the shop, get the Jonsered, return to the tree and finish the cut.
Then back to the shop and a little exploratory surgery on the Stihl revealed the rim sprocket is torn at its edge and the brake band is hanging out of the narrow slot between the rim and the saw body.
I removed the rim and was able to slip the brake band back inside. The damaged rim is a problem and I don't know how the brake band is supposed to be attached properly .
My question is can the brake band be serviced with the clutch still attached to the shaft or does the clutch need to come out to service the band.

I cleaned all the gunk out of the clutch area and found that the band just clips in and can be easily removed.
I got out the band in 2 pieces and pulled all the brake related stuff including the handle and buttoned the saw back up. It runs but with no brake.