Geeetech A30 X MGN12H Linear rail mod

I designed everything for use with my petsfang and the original carriage. My carriage has a large hole in the center (v3.3 A30). So I couldn't simply drill it

You need a 400 mm MGN12H rail + block. You can use the original belt:
https://s.click.aliexpress.com/e/_c4KPXmRV

It should also work with A10 and A10M. Please confirm if you try it

A10 and A10M require a 300 mm rail: https://s.click.aliexpress.com/e/_c4KPXmRV

There are 3 solutions:
A - the one I used and tested. It consists of the original carriage + printed plate + modified Petsfang + X endstop

B - full cage only to be used without the original plate. With this solution, I did not design the X endstop. (You could try this mount https://www.thingiverse.com/thing:3094482 ) I have not tested it

C - plate to be used with the original carriage and original cage + X endstop. You can also use this plate just for drilling. I have not tested it

With solutions A and C, it is not essential but recommended to print spacers for the belt, so that the belt is perfectly aligned. In this case, you need to print an X_motor_spacer for the endstop. You probably need a longer belt. I don't know because I replaced the belt with a stronger and better one anyway

Regarding the endstop, if you also plan to modify the Z-axis with MGN12H, you can directly install the mount for the X motor with endstop. You can find it here:

https://makerworld.com/it/models/2544358-geeetech-a30-z-mgn12h-linear-rail-mod#profileId-2801525

For the MGN12H block, 4 M3 screws are needed, and for the rail, 3 or 4 M3 screws + M3 T-nuts

https://s.click.aliexpress.com/e/_c3lRasGR

https://s.click.aliexpress.com/e/_c3N40GfV

For a precise rail installation, you can use this guide:
https://www.thingiverse.com/thing:2152669

Here is a demonstration video:
https://youtu.be/vFeug0_gQI4