Trying to understand execution times vs shift register clocks

[Dennis Zabawa]

This is the program we load in (assume any non-programmed memory cell = 000):

000   001  A
001   000  B
002   100  X
003   004  PC
004   007  ADD A IND/INDX
005   376
006   000
.....
020   125
.....
225   030
.....
376   020

We press START:

The execution starts at 004
The operation is to ADD a value to the A register using indirect/Indexed addressing
The next memory address contains a pointer to the memory cell containing the address of another memory cell - 376
The contents of that memory cell are added to the X register to derive the address of the memory cell containing the value of the operand - 020
X register = 225
The operand at 225 = 030
The operand is added to the contents of A register - 001
The next instruction is a halt
At the end of the program the A register then contains 031

Considering that each bit of each byte of memory requires a clock pulse, how many shifts and how long would it take to execute this program?