Rubber hangers, did you apply rubber or tyre mounting lubricant, it makes a world of difference removing and installing those hangers. Anti seize compound also your friend applied to every joint, bolt, stud and nut for easy future removal. Nickel based compound good up to 24 to 2,600*F.

Congrats, your up and running again but had to ask, is it now too quiet now having a resonator plus muffler in the system? Ditch one or the other which other sounds better. Manual trans vs automatic allowing a wider range of rpm's vs automatic with low rpm shift points not allowing the engine to sing, rather sad.
Even a Vibrant stainless (no rust out) resonator their "quiet series" will tone down a too loud of system. Not some high school muddy sounding Flowmaster 40 series crap.
Thinking a system having excessive back pressure like the factory with elevated exhaust heat being trapped not being nice to Mr. exhaust valve as they are already are being punished (torched) by the overly lean fueling system tuned to the North American market.
Borla gave me the right musical exhaust sounds I enjoy lead footing it but still able to be quiet enough a passenger can take a nap down the highway. It's a system not silent also not like some stupid sounding high school kids vehicle thinking noise means fast. I was looking into a stainless (million mile warranty). Installed it w/cat back stainless 20 years ago, no rust out problems to deal with even when used as a soccer vehicle of 10 years in stop and go town traffic. I keep my vehicles a long time hence stainless pays for itself vs several replacements. The LR engine has been much happier now breathing freely releasing a few more horses allowing pulling strong up to redline if need be but not necessary. Warmed over 4.6 transplant not wanting the D1 to be the slowest turd on the road, sleeper comes to mind.
With your horn remark I installed a 27" long Grover air horn that has a 8 1/2" diameter bell at the end. Only the bell sticking out of the air dam window pulled back tight against the dam slot at the bell. The horn diaphragm end is just over an inch clearance away from the front diff axle. Black wrinkle finished exposed bell end blends in with the black air dam but also facing forward into free air allowing maximum sound blast effect. Sucked up tight just clearing under the oil pan mounted on a piece of 1" x 1/2" channel bolted to the front cross member.
Air supplied by a 18 1/2" long x 8" diameter air tank (930 cu/in or 3.80 gal) 140 to 160 psi on the ready. Tank is mounted under the body just ahead of the driver's door latch area tucked in high just above the bottom of the frame rail, out of harm's way. Wimpy beep beep LR horn in town, mini under dash switch to the modified propane valve bolted up inches away from the horn diaphragm ready to blast away. It will get your attention including idiot drivers (careful not blasting the elderly). My area we have a lot of "i'm bigger i'll run your azz off the road" truckers but they respect their own sounding air horns when blasted and for a reason only. It's a harsh but deep sounding attention getting horn, highway patrol included. Was used properly by the officer who visited my home a week later. He has a motor home wanting to know how I installed the horn and where to get the parts. Cool office also a Norton collector like me......~~=o&o>......

 

My loud exhaust days and re-thinking the factory are over. Just want to drive down the street and get to work and back with as few problems as possible. And avoid those pesky flashing lights that want me to stop and talk...

 

Factory sounding LR wanted it to be totally silent wanting to grab their share of the "Luxury SUV" market. Stuffy and heavy yes but can't have it all.
In regards to "Party Light's coming up your six all the time due to "loud exhaust", I haven't been stopped once in 20 years by pulling away hard, passing or going opposite direction lets say in 2nd or 3rd gear 3/4 to full throttle 2 to 4,500 rpm's with the Borla cat back system. One local Sheriff pulled me over wanting to know what exhaust I had as he has an older RR a full on dirt not street licensed vehicle if that counts? Not an issue per state maximum dB's allowed tests. Only mod made with the 2 1/4" exhaust stepping out to the 4" bell tip was to cut back the 2 1/4" tubing that used to extend flush to the end of the 4" bell. It looked stupid plus the very very slight gas velocity reduction and vacuum pulse created utilizing that larger stepped diameter. Down the highway 2,400 rpm's plus totally silent in the cab. Trust me I know about 3 1/2" exhaust kicked out 45 degrees duels just ahead of the rear tyres in the Pick Em Up behind a 484 cu/in engine on a 2- 6 hr highway trip creating ear and body fatigue results.
Only disadvantage the bell end keeps turns slightly tan coffee colored vs keeping the polished bright stainless finish I maintained. This due to the exhaust heat and volume the engine's passing 11' from the engine due to better flowing heads and exhaust system i've created all pointing to it generating more horsepower. Mild head porting plus common sense cleanup of factory production heads. Port misalignment intake to heads, heads to exhaust manifolds LR wins the trophy the worst in the automotive industry period.......~~=o&o>.......