What blocks are there to see anyway? Nothing, right?

In the world of stamps, most collectors immediately think of blocks consisting of four or more stamps torn from a sheet or small sheet, containing one or more stamps. However, while reviewing my Indonesia collection, and specifically the section covering the period of the struggle for independence from 1945–1949, I came across a series of overprinted stamps from Sumatra. It concerns the series of five values ​​issued in late 1946, early 1947, without inscription. Kemerdekaan FundFour of the five stamps were also printed in other colors. In 1947, stamps from Sumatra were issued in the previous year, bearing an overprint of a value, sometimes in sen, sometimes in rupiah, and sometimes in guilders! The block then served to obscure the original value. But how should this block be viewed? Which one is upside down? Let's first take a look at a few stamps from the series. But that doesn't make me much wiser either. My gut tells me that the block on the right stamp of the pair is positioned correctly, while the one on the left is upside down. But then those blocks on the 50 sen and 1 guilder stamps are also (coincidentally) upside down. Or should it be the other way around? Then there is the 1 rupiah stamp on the 40 sen. Here I am completely lost! Magnifications give me a better picture. But what do I find? Upside down, to the left, to the right—how am I supposed to proceed now? There are still a few series to look at. First, a series of four applied prints. And these four, again according to my intuition, are all positioned well. A reassurance? The next series consists of two stamps that have been changed into airmail stamps due to their overprint. And what do you know? Both the 10 rupiah and 20 rupiah values ​​are the opposite again. Both upside down? No, I thought one overprint was correct. But we are persevering. One more series to go. Overprints on the old 40 sen stamp in red with the inscription Fonds Kemerdekaan, crossed out with one or two horizontal lines. Apparently, they still had a large stock of this stamp lying around, even though some of it already bore the overprint Pos Udara and 10 Rp. The 30 sen stamp has a block that feels normal. The four other values ​​have a larger block imprinted over the old value. Am I getting anywhere now? Apparently not! Who knows the solution? Which position of the block is correct? A small collection, but worth diving deep into! Will you dive in with me?