As far as the tire size goes, I guess I would go with Nitto. They know what they sell. That's tough though man cause it's a big difference.
To figure how far the wheel/tire will stick out:
The stock wheel is +19 offset. If you go to a -12 offset, the difference is 31mm or 1.2" (25.4mm = 1 inch). So your wheels will stick out 1.2" further.
The stock tire is 275 or 10.8" wide. The 295 is 12.36" (according to nitto)
This tells you the new tire will be roughly 1.5" wider. (.75" on each side)
So just add .75" and 1.2" and that's about 2" further than stock setup.
If you use the tire size we figured (11.6" wide) instead of nitto's, it should only stick out about 1.5" like your rim guy said.
With a 0 offset, the wheels will only be about .75" further out.
I'm sure there's a website that will calculate this for you, but i haven't found it yet. I hope this helps.
I don't have any pics looking down the side, but the tread on the tires lines up perfectly with the fender. The sidewall may stick out a lil bit further. I would go take some pics but it's been raining all day.
The rear spacer was $54.95. Don't remember how much shipping was.
I hope this is helpful to you man. I am by no means an authority on anything, just sharing what I learned through my research.