It's tough honestly. There were a lot of big changes going on with laptop display technology through the mid 90s, which stabilised around 2000 - where TFTs (TN panels 😀) and 3.3 LVDS signalling became quite standard.
The mid-90s laptops can be DSTN (which has a couple of different types) or TFT, and they can use either 3.3v or 5v signalling. You can't safely use a 3.3v display if the laptop is sending 5v to it. Mountings aren't very well standardised outside of the 12.1" 800x600 screens, so it can be necessary to modify LCD mounts.
To send the display data, some of them, particularly older ones or cheaper ones will be using parallel (one wire for each colour bit) and later / higher res ones using LVDS (multiple wire pairs to pass the same colour data over high speed serial links).
I've been fixing screens on my Toshibas and other laptops for a while - getting the originals isn't even possible anymore.
So for one of them I've had to use a voltage regulator to convert a 5v display power to 3.3v for the more easily available 3.3v panels.
On another one, I used a 12" LVDS TFT the same type as the original Toshiba one, but it was from a different manufacturer, so I had to re-wire the whole connector working out what's what from where the wires go - datasheets that define the pinouts are quite hard to find for older laptops.
Recently I was looking at getting a cheap 5.6" parallel TFT to replace the LCD in a Toshiba Libretto 50CT - they both use parallel signalling, but then I worked out that the Toshiba LCD is only 4-bits per colour, new LCDs don't know what to do with that, they're 8-bit or 6-bit per channel. So that's a no-go for now. And the timing has to match , idk how that works at all, I'm not an EE.
Converting DSTN to TFT is downright hard - DSTN is using two separate display signals for each half of the screen. Some are parallel, some LVDS, so you can't just connect a TFT (or oled, or IPS) to that directly. Yyzkevin on this forum and some hardware hackers in Japan have been doing some work with just that though - retrofitting the IBM PC110 palmtop's DSTN panel with a commonly available TFT.
It looks like it requires BIOS changes (to tell the video card to send to a different panel type) and different screen cabling, along with something to power it all: https://www.yyzkevin.com/tft-update-january/
Upgrading to IPS is possible, but finding IPS panels that fit the screen area/resolution is hard. The laptops after 2000-ish you can do a lot more with - this Thinkpad X61 is a later example but it gives a good overview of modification even with similar parts: https://ithinkpad.wordpress.com/2011/10/14/x6xipsguide/
