I have an a3000d motherboard here that needs a fat agnus and a denise. The motherboard is marked "REV 6.1 MOD". I have another, bad, motherboard (rev 7.1) with a chip numbered 8273AB in the fat agnus socket and one numbered 8373 in the denise socket. Assuming these parts are good (no way to test other than to try them, I suppose) are they likely to be compatible with the earlier motherboard? Even if they are, do I ideally want newer revisions of these chips?