BTW, if you end up with Edelbrock Performer heads they use 2 of the oddball long head bolts on each side instead of the 1 on each side with the stock LA heads. New Edelbrock heads come with an extra bolt in each box for this purpose so you can get by with that and a standard ARP head bolt set. But, to be safe with the Edelbrock Performers, you can order a different SBM head bolt set that has 2 of these special bolts for each side. (Hope this makes sense.)