from io import StringIO
import pandas as pd
df = pd.read_fwf(StringIO(
    """0    0CF00400 X       8  66  7D  91  6E  22  03  0F  7D       0.021650 R
0    18EA0080 X       3  E9  FE  00                           0.022550 R
0    00000003 X       8  D5  64  22  E1  FF  FF  FF  F0       0.023120 R"""
    ), header=None, widths=[1, 12, 2, 8, 4, 4, 4, 4, 4, 4, 4, 4, 16, 2])
Reading a text file using Pandas where some rows have empty elements?