Sinclair C2037 Cavity Filter Tuning: Cable Lengths

I'm tuning a resonant cavity filter set (Sinclair C2037) and I need an explanation of the cable lengths.

See my ASCII diagram:

. Antenna 50 ohms

. |

RADIO <---> Passband filter <---> Passband filter <---> Passband filter <--|

. |

. Reject filter <---|

. |

. 50 ohm load

. or next group of filters

The Sinclair book indicates that the cables between Passband filters are 21 inches for 145 MHz (RG214U w/ Vf=0.66).

Also, I read that the length from the reject filter to the Tee junction at the Passband filter is a quarterwave length long (assuming that the reject is a short at the intended frequency). But my buddy says that he always uses a 4 inch cable, connected to a T into the last passcan and the reject filter. Between each Tee is 10.5 inches. So I now measure about 4+10.5=14.5 inches from the reject filter to the point where the antenna feedline connects. And I'm not sure why the 4 inch cable is added between the first passband filter and the T.

Can someone layout the actual engineering rules?... i.e. lengths should be half wave between passband filters, and the cable from the reject to some point is a quarter wave .... of course, correct my starting assumptions if they're wrong.

In the end, I'd like to be sure that the cables I cut are the correct size. The frequency of interest is 145 MHz, and the cable is RG-214U with Vf=0.66.

I have a sweep generator and SWR meter, if you also want to add in some tests that I should perform.

Thanks,

Greg