Your working sets should be different percentages of your training max for each set. For example, the first set of 5 should be at 65%, the second set should be at 75%, and the third set should be as many reps as you can get at 85%.
If you are listing what you are currently working at rather than what you think your sets should be in 5/3/1, then you can calculate what your maxes would be by:
(Weight X Reps) x .0333 + Weight.
So for your deadlift, your estimated max would be (375x5)x.033+375, or 436. Your Training Max would be 90% of that, or 393. That's the number you would use to calculate your working sets.
I'm not sure I understood your question correctly, but I hope this helps.