I'm also in the process of doing the Lebaron upgrade and like others, having some trouble finding the studs used. Everywhere I search it shows Dorman 610-323 studs to use. Well, numbers don't always match notrth of the border, so I've been looking into what vehicles use them and what else can be used. So far I've come across these:
Dorman 610-323 used for:
Camaro, Corvette, & Firebird
ARP 100-7708 (summit racing site) has a knurl of .509, some say it's slitely to big of a knurl
ARP 100-7709 has proper knurl of .485 but only sold in sets of 4

(honda)
1996 Chevrolet Cavalier:
12x1.5mm
.480 knrul
55mm in length
Napa 641-1581
12x1.5
.323 knrul
54mm in length
I'm inclined to check out stock on the cavalier, since they are a dime a dozen. Probably get one from a wrcker to confirm first.
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