Just an FYI but no they did not stop selling them due to "collecting dust". I had mine on order for my hemi Dakota swap for 8 months before receiving an email telling me they had to refund my money. After 3 hours on the phone griping I was transferred to the head of R&D and was told that the EPA will no longer allow them to sell them. If you take a minute and look up the RPM act you will understand. He told me they had the headers, holley had been in litigation with the EPA for months (reason for the backorders) When the 2022 congressional year came to a close and the RPM act had not past holley started refunding money. They even had to change the website which is why the D100 now say 72-74 because after 74 the EPA's clean air act makes modification of any kind illegal. The swap headers fit all the way to 93 but they cant say that now. Even for vehicles used off road or in race settings. The law has not changed a word since 1974 but the new governments interpretation of it has. Look up the RPM act.