Tires: P to LT tire replacement, nissan titan crew cab, 2005 nissan titan

Question
Is the following a unsuitable replacement tire for 2005 Nissan Titan Crew Cab, Off Road Pkg.
LT285/70R17 D load
OEM was P285/70R17 35 PSI
I calculate that I need to run @45 PSI to achieve same load rating as OEM P285/70R17 (Max Load=2833 lbs  at 35 PSI). If I devalue 2833 by 10% = 2575 lbs.
The replacement LT285/70R17 would require 45 PSI to achieve this same load.
I contacted the manufacture BFG and they recommended 55 PSI. (they must not devalue the P Metric tire in their calculation).
My question: is it unsafe to inflate at 35 PSI to make the ride and handing better.  Max load at 35 Psi is 2105 lbs. My vehicle weighs:
GVWR 6522 lbs
GAWR fr. 3500 lbs
GAWR rr 3800 lbs
Should I try to return this tire(purchased a week ago) and buy a P Metric tire?  Your opinion is appreciated.

Answer
Brad,

First you are to be congratulated for doing the methodology correctly.  Now let's see if you got the details and the calculations correct:

According to Tire Guides, a 2005 Nissan Titan 5.6SE/LE with the Off Road package originally came with P285/70R17 inflated to 35 psi.  This exactly matches up, however Tire Guides says the GVW is 6499, but the difference is small enough to ignore.

The rated load of a P285/70R17 at 35 psi is 2833# and derating the tire 10% because it is used in a light truck application results in a load capacity of 2575#  (so far so good!)

The load table for an LT285/70R17 shows a load carrying capacity of 2755# at 50 psi and 2510# at 45 psi.  If we interpolate between the pressures, the tire needs to have 47 psi to carry the same load.  (Yes, I agree, BFG did not factor in the 10%, but I wouldn't be too hard on them.  This is not a well understood technical quirk.)

Now to answer your question:  "Is it unsafe to inflate at 35 PSI to make the ride and handing better."

I tend not to think in terms of "Safe" and "Unsafe".  These are black and white kind of words and how do you determine where the diving line between the 2 are?  Instead, I think in terms of "risk" - which is easily understood that there isn't a clear dividing line.  

So let me put it this way, there is a risk and you can calculate how much load the tire can carry at that pressure.  Officially, I can't condone the practice, but you know that the LT tire is built out of stronger materials, which might be helpful to avoid penetrations in off roading situations. All I can tell you is you would not be alone.