@Red
Not sur what you are trying to do ?
Do you have old 512k Agnuses (sounds odd) ?
Those that came in Pal OR NTSC ?
Or do you want to change the default setting on a 1/2mb Agnus ?
Putting in a PAL-Agnus should do the trick in the first case, and in the 2nd you
would need to disconnect on pin which is on ground in NTSC systems.
(I could check that in detail if needed).
Also remeber that real PAL-Amigas only run at 7.09 instead of 7.14mhz :-o