homemade 4 bar setup???

[69charged]

hello guys. i was wondering if anyone can tell me how hard it would be to make my own 4 bar setup? i mean, someone who has done it before and what to look for and such. i work in a full complement machine shop with our own welder and all so that is not an issue. im asking geometry wise what would a guy look out for.
any help would be great.
oh by the way its going in a 5.7 hemi powered 69 charger. if that makes any difference.

thanks
clarence