A-body low tension hood springs for bolt-on fiberglass hoods

Would these hold up a Fiber Glass 1973 Duster hood with a dual snorkel scoop bonded on to it? Or a full fiberglass Sixpack Hood from AAR?

They should - all depends upon the weight of your hood. Who makes the bolt-on fiberglass hood you have and what materials did you use to bond the dual snorkels to your hood? Do you know the overall weight of your modified hood?