FWIW, This is what Kevin at Upscale says about putting KT88's in a specific ARC amp.
"ATTENTION! We are no longer re-tubing Audio Research VT100 amplifiers. Mk1, Mk2, Mk3... doesn't matter... no exceptions. "
"ATTENTION! We are no longer re-tubing Audio Research VT100 amplifiers. Mk1, Mk2, Mk3... doesn't matter... no exceptions. "