I haven't seen any photos of the GLHS. I just saw my brother last night and he was telling me about it. I don't know that he has done anything cosmetic to the car yet, just a new clutch, axles, and shift linkage. If I go with him to Thunderhill, I'll take photos.
I had another thought about your mufflers this evening. My friend had glass packs welded into the tailpipes of his 67 Barracuda after he got tired of the resonance. It quieted it way down. You might look into that.