If you searched the part number (CSTCE10M0G55) found in the library, you will see that Sparkfun only made this footprint for 10MHz or 16Mhz resonators. But, when you see the resonator on Mouser, for example, the dimensions are 1.3mm x 3.2mm. So you need to find a SMT 8MHZ resonator that has the size of 1.3mm x 3.2mm. There is only one that pops up on Mouser. http://it.mouser.com/ProductDetail/AVX/ … 0J8w%3d%3d