Holley/Demon Carb stumble

All my parts are ordered and the last piese will be here on the 31.

What, and where, should i be looking for damage to the $5.00 metering block i got off of e-bay.
How will i know it worth trying.

YR said something about it could be a alcohol metering block. but after i bought it the description of the part when a way as it was sold.