@GODFFERY how about throwing up a pic of your banjo solution on this thread for anyone e who wants to contact you about it.
For some reason I've not had much luck with posting pix to this forum, for over a year or more now?
Here is the basic rundown:
Enlarge the hole of the internal flair fitting with a #30 / 1/8" drill bit, Tap that hole with a 4mm thread, screw in a long 4mm bolt, mount the caliper in a bench vice, pull the bolt out with a firm yank, (slide hammer works best for this) Once the flair is out, carefully drill the tapped hole about 10mm deeper, using a 8.5mm bit, (be sure not to go threw into the piston bore) then you can tap the hole deeper, first using a standard tipped tap, then fallowed by a bottom tipped tap. Now here is the critical part... You must now use a banjo crush washer that has a small enough O.D. that it will recess into the counter-bore of the caliper surrounding the threaded hole. In a pinch, You can just file a larger one down on the O.D. till it fits. (If you don't do this, the banjo fitting will not seal properly)
For anyone not feeling comfortable with that modification; (knowing if done wrong will produce a vintage paper weight) Then I do perform that service, as an option, with the order of a fully refurbished Caliper. (Core exchange discounts available)
https://godfferysgarage.com/