I refilled mine exactly the same about 6 mos. (& 10k miles) ago. Same 2 qrts. and some ran out before I put the plug back in. No problems. In fact I didn't really notice it at first, but now it shifts noticibly smoother (especially first to second gear) after switching to Redline MTL. If you put in less than 2 quarts I don't think there is any way you can do any harm.
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