I have a Williams target peep sight on my Winchester Model 94AE but the aperture is rather large, i.e I see a large circle through it. I would like a smaller aperture, but I am not sure what size. How can I find out which one I do have so I get a size or two smaller? On a side note (as I do not think it matters on the aperture choice), I am not sure whether my peep sights are the FP (aka foolproof) or the 5D. How do I find out? Any help on either of the questions is much appreciated!