I have no clue what the re-occuring topic problem is with Ruger's ancient take down system. As a sub-10 year old in the 1950's, I picked potatoes at 5 cents a bushel until I collected $37.50. The local hardware ordered me in a Ruger RST-6. The Ruger Standard Model 6" .22LR of the 1950's.
I actually read the paper instructions.
The first day, I sat behind my house and burned a brick of Rem22LRHS 40grain ammo of the era that may not yet have been called Golden Bullets, but I had a case of them copper plated as they are today. Earned the case at 5 cents a bushel.
The gun was dirty.
It was cleaned and re-assembled that day by a 8 or 9 year old. The same continued periodically until the guts of the gun were so worn out it was approaching unsafe. Roughly a case a year for 20 years. It then got tossed in the back of the safe. A Competition/Target 6 7/8" version replaced it. 30 years later, Ruger rebuilt the RST-6 to new and refinished the metal at the factory. At only four times its purchase price. But I digress.
The only "trick" to the re-assembly process is to actually look at the tang of the hammer strut and SEE IT ENTER the little groovee in the top of the hammer spring assembly as you close up the system. If you actually watch it close up in the right spot, there is never any error. But then again, I could read fairly early even in Bubba Land.
To get the receiver off the frame, wack the end of the barrel with a soft shoe. To put it back on, wack the back of the receiver with the same soft shoe. Or as an adult, use a rubber mallet with no metal filings in it.
The new Mk.IV falling apart as you open it is for sandbox vets. Guns that fall apart are not really needed if you understand the system of the older ones.
(This topic occasionally surfaces. Usually in the format of the gun is too dirty to shoot and too hard to clean properly. The above post contains specific (1) context, (2) experiences, and (3) two separate suggestions for dis/re-assembly of the exact firearm system. A young kid that reads the instructions can do it correctly. Reading was an essential skill in the 1950's and is still a handy life skill. YouTube had not been invented yet to replace reading manuals. Ruger did and continues to supply very detailed dis/re-assembly instructions with their firearms. They really should be read. Their web site has automatic links to the same exact instruction manuals model specific should the original be lost.)