Dartfreak75
Restore it, Dont part it!
Here are the numbers I got off my heads these are 360 587 heads. The .487 lift is the max before and clearance added i would add at least .020 for clearance so that makes your max lift .467 my heads had a shorter install height than the factory claims so other heads will vary you just gotta check yours.
Spring height 1.62
Guide to retainer with seal .487
Gtr without seal .614
Spring height 1.62
Guide to retainer with seal .487
Gtr without seal .614