Elesar Parallel Port Driver for RT Kernel

I am trying to get a Pi set up with a parallel port and then use LinuxCNC to control a couple of Clearpath servos for a lathe conversion.  The Pi is a 4b with 4 GB and the parallel port is a HAT made by Elesar.  (Maybe I should have just gone straight to a Mesa card instead). I successfully installed an OS with LinuxCNC (I believe this is the image I used: drive.google.com/file/d/1IhrrdGRNvsdclVi.../view?usp=drive_link )  but the drivers for the Elesar HAT would not install.  Worked with support at Elesar but they finally concluded that drivers for their board would have to be compiled for the specific RT kernel. Here’s their latest reply to me:  “All we did to produce the 6.1.54-v8+ drivers was to follow the instructions on the driver source code page  github.com/elesar-uk/parport-sphat .  The key bit is the initial step rpi-source which downloads the source code to the corresponding Linux kernel. Without that you can't make a matching driver, so if you know where 6.1.54-rt came from and the source code is available it should just be a case of following the remaining instructions on the parport-sphat page to build a driver.  Or if there's a mailing list supporting the real-time kernel perhaps a friendly developer who already has the source code could compile the driver for you?”  Can anyone help me get the source code for the image I installed so Elesar can create a driver or help me create the driver given their instructions above?  Unfortunately, I am a beginner with RPi, Linux, and LinuxCNC so may need a bit of handholding.

If the parallel port hat is just providing buffering
for GPIO bits, you may not need the driver
(which is a printer driver which LinuxCNC does not require)

LinuxCNC can use GPIO directly

Ok, but I don't even know how to test this out. I believe the driver is needed for LinuxCNC to recognize the PP. Are you saying that I would just use the LinuxCNC GPIO driver then determine how the signals map to the DB25 connector on the HAT by experimentation? I probably would need to be able to use the PP configuration wizard given my inexperience.

LinuxCNC doesn't need a parallel port driver at all.
(It does direct hardware port access on a PC and this makes no sense on a RPI)