First of all, iirc you asked about the difference of elimination and clearance a few weeks ago, right?
Here's something from the book "Biopharmazie" by Langner and Mehnert, 5th Edition:
Elimination (Abfluten), schlie?t den Metabolismus und Ausscheidung (Exkretion) ein
Clearance gibt den Teil des Plasmavolumens an, der pro Zeiteinheit durch einen bestimmten Prozess (z.B. renale, hepatobili?re oder metabolische Elimination) oder durch globale Elimination (Summe aller Eliminationsprozesse, Gesamtk?rperclearance oder totale Clearance) von der betroffenen Substanz v?llig befreit wird
Elimination scheint das gro?e ganze zu sein und Clearance ist i.d.R. nur ein Teil davon bezogen auf das Plasmavolumen, kann aber im Fall der Gesamtk?rperclearance eher ein Synonym der Elimination sein
You should keep in mind that diclazepam has a very long half life even compared to clonazepam so it will accumulate until a steady state is reached but I don't know how you can calculate this from the relations of potency/duration/accumulation etc. and it's further correlations with the increasing tolerance due to accumulation
All the calculations are based on
this paper, but this is preliminary data with N=1, plus they bought pellets instead of synthesizing the diclazepam themselve/buying it from a trusted source like S-A, so
the amount of diclazepam per tablet ranged from 0.59 to 1.39 mg (median: 0.95 mg, mean: 0.94 mg, SD: 0.23) (n = 13)
Here's the data I worked with:
The highest concentra-tion of diclazepam (3.4 ng/mL) was detected in the sampleobtained 3 h after the intake
Volume of distribu-tion and clearance were 8 l/kg and 165 mL/min
VD for a 70 kg person is 560 l
Now first of all I wanted to check the half-life for shits and giggels

One can use this equation: t1/2 = (0.693 * VD)/CL = ( 0.693 * 560000 ml) / 165 ml/l = 2352 min = 39.2
Given that this is only an approximation I'll take the 42 h
Now for steady state (Css) I used this equation: Css = D / (DI * CL) with D=dosage; DI= dosis interval and CL=clearance
I'll do it for 1 mg every 24 h
Css = 1 mg / (24 h * 165 ml/min) = 1 mg / (1440 min * 165 ml/min) = 4.2 * 10^-6 mg/ml = 4.2 ng/ml
This is around 1.2 as high as the peak plasma concentration after a single dose of 1 mg which seems about right.
The steady state is reached after 3-5 * half life, so 3*42h - 5*42h, so around 5-9 days
If you want to reach steady state earlier you can start with a loading dose (usually the loading dose shouldn't be too high due to side effects etc, but we're talking about benzos so a huge therapeutic range and the dosage isn't extremely high)
D(loading) = VD * c = 560 l * 4.2 ng/ml = 560000 ml * 4.2 ng/ml = 2.3 mg as a loading dose
Now this is all based on a single paper with a single man taking a diclazepam pellet, so I'd be cautious. And keep in mind, those are just some numbers that don't represent real life completely. Everyone reacts different so it's important to look at the bodies reaction as well, like tremors/shaking, heart rate and blood pressure and dose accordingly