I’ve started the process of raising my cabs using Amazon risers, there are hundreds listed, you can shop around and find them for $25.
https://www.amazon.com/gp/product/B07RMX6MBR/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
I had some left over U channeling to even out my cuts since I’ve never cut foam or used a hot knife.
https://www.amazon.com/gp/product/B07DCDV757/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Foam board enough for 3 cabs – front and 2 sides
The results are great so far, I can see the entire screen, never having to lean back. I have some cabs that have horizontal 17” stock monitors with screen tilt that don’t have issues with screen visibility, but this really helps out with 20” screens and vertical screens.