Classic Retrofit fuse block has no power to two fuse terminals?

[TrickySF]

I have installed the front and rear fuse blocks with no difficulty but find that terminals #16 and #21 (counting from the front of the car) have no power to them. Any ideas about what would cause this? Anyone know of a link between these two terminals? Since the wiring is very tight, I would rather not try to remove the block to look at the back of it. Any comments will be greatly appreciated.

[timmy2]

Normal.
16 is fed by a jumper for later years. (Fuel pump relay)
21 isn’t used unless it has power Windows and is fed with a black wire from the PW relay.
Your car a 74?
Here ya go.
https://www.dropbox.com/sh/s292jtsyvl6llw2/AABF-ofgMfoMltGa99Asphr5a?dl=0

Supplementals for options:
https://www.dropbox.com/sh/hr6dquonkwjp23a/AABjbboPo-4J2L9nBoC5tbh6a?dl=0

[TrickySF]

Thanks Timmy2, as usual, for the quick reply. You are always most helpful and appreciated on this forum.