Strocky,
Yes, I read that, but it doesn't answer the questions I put to you.
If you undo the 4 screws holding the CPU cooler arms to the motherboard:
(1) Can you then loosen off the brackets holding the pipes to the side of the case ? Yes / No ?
(2) Does that then allow you to slide the pipes along the side of the case ? Yes / No ?
(3) Can you loosen the 4 black screws on the top of the CPU heatsink which clamp the pipes? Yes / No?
(4) Does that then allow you to move the black heatsink closer / further away from the side of the case ? Yes/No?
The heatsink and and pipes are designed by Streacom to have adjustable positions which once in the right position you then clamp down to hold in fixed position. This allows a variance in where the heatsink sits. Your first post shows ability this from the image attached - Standard heatpipe area in light purple - SH2. <- thats the area the heatsink can be moved around in (by loosening the clamps on the pipes) to meet the location of the cpu holder. AM4 boards are generally not that different in position from intels ... as below ... ( your existing board and new board side by side ). You can see there would be minimal adjustment of the position needed.
What is different is the holes around the cpu that coolers screw into. In your case the 4 existing arms sticking out are not going to match and AM4 set of holes on your new board, and that Streacom do not offer a direct alternative - I get that ... but you can over come it. Yes - it might need a little modding, but its going to be within the scope of you i'm sure.
I would make use of the Streacom Universal CPU Mount to overcome this:
https://streacom.com/products/um2-universal-cpu-mount/
Remember all you are needing is for downward pressure onto the top of the heatsink to press it onto the CPU. This UM2 piece looks like it would do that for you.
Once you have taken the parts apart (which you'll need to do to remove the motherboard I presume), I would
a) Cut the arms of the existing CPU heatsink . . . hacksaw + a small file to smooth it.
b) On the new board remove the 2 AM4 plastic brackets on the top of the board, but leave the bracket on the underside . i.e. unscrew the 4 screw marked in red, and take away the plastic bit between them.
c) get the UH2 and place it over the top of the whole black heatsink section and adjust the arms so that they sit over the holes of the AM4 motherboard, and use longer screws/bolts to reach down through the arms and screw into the motherboard mounting holes. i.e. move the pink dotted arms to over the red dotted holes.
I imagine you would need longer bolts, but the threads will be a standard size. Most hardware stores should be able to see you right. You can take the screws that you removed earlier to find the right thread size needed.
Yes, there this would be a little modding, but its not crazy stuff either and would get you the result you are looking for.
A potential issue might be height. How much spare height is there above the existing black heatsink to the top of the case ? If you are out of space there, then some other mods / adjustments may be needed.
You could file down the top fins of the black heatsink, or I can think of a different design of clamping bracket that would do the job as well, but would be a much lower height. ( but would be more complex to make.
