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Today I started installing a 130amp 3g alternator with the 7" ear spacing. I read everything I could before starting and thought it would be a drop in with some straight forward wiring. Here is my $.02 for those with a '69 and with a 351w. These cars have different alternator brackets from all other years I understand. You WILL need to fabricate an intermediary bracket for the lower mount. The 3g case (specifically the 8mm bolt) interferes with the cylinder head alternator mount bolt, the one on the right side. It interferes to much for an easy fix. This means that the alternator can't swing far enough towards the lower bracket for the bolts to go in (even though the spacing is correct). This also means your old belt won't work either. I'll save you time and let you know that the intermediary bracket should have its holes 3" apart center to center, and it should be thick steel like the factory brackets (~3/8" thick I believe). You will need to either make or find a spacer to take up the extra depth created by the intermediary bracket to keep the pulley straight. My last advice: don't bother messing with clocking the alternator case differently for 2 reasons. It's difficult to do (I gave up after doing exactly what I read other people did) AND you can break the aluminum case. It's nearly impossible to do without marring up the aluminum. One more reason not to bother is that if you do need to get a new one for a late model at the regular part store, your wiring would be setup for how you clocked it and not how they are when you buy one. Hope this saves someone some time!