Ok, start with A=1x10^10 a nice enough round number
T = A cycles of radiation corresponding to the transition between two energy levels of the caesium-133 atom.
L = length of a side of a cube that holds A molecules of pure water at sea level at the melting point temperature
**All below are derived from these 2 measurements and the number A**
V = L^3 the volume of a cube of sides L.
M = the mass of V of said water.
Q = A electrons
F = the amount of force needed to accelerate M mass at L length per T squared
W = A force of F acting over a distance L in the direction of L
I = Q charge flows in T time
P = one W per Q
R = the resistance needed to allow I current to flow at P voltage
C = the heat emitted by a resistance R under P voltage for T time.
many more but you see how everything is based off the nice round number 1x10^10 and two easily verified physical measurements. I believe most everything could follow.