Chainsaw Repair

I have 360T, CS345, and CS450.
Have owned them since 2005 and 2006.
No complaints.

What mods could/should I make to them?

Great saws, but I've always been open to a little hotrodding.

I'm guessing cut the deflector and add a second outlet port to the muffler, and remove the limiter caps on the H and L screws to allow more screw adjustment?

Are there any other specific muffler mods I should make?
I don't know it 2005-2006 models had cats in the muff or not.

BTW, thanks for the reply.
New to chainsaw forums.
New to chainsaw modding.
Not new to chainsaws.
Not new to engines, nor modding of engines.
professional mechanic since 1991, just not a professional OPE mechanic.
Strong mechanical background. Still have much to learn (ain't dead yet).
Above average intelligence with a thirst for knowledge and a burning need to hotrod everything I own.
Or, at least, improve it over its choked-down, OEM configuration.
Willing to listen and eager to learn.
My saws are used by me and me alone.

Can I run the narrow kerf chain with stock bar and drive sprocket?

I've run a regular. 325 chain on a NK bar with no problems.
NK  chain on a regular .325-.050 bar, would be a problem when the cutters are filed back half length not allowing kerf clearance.