Dodge Demon ball joint question

I have a 72 Dodge Demon. It was converted to the bigger upper ball joint I guess 73 and up Duster. When I purchase the lower ball joint do I have to buy it for a 73 Duster also? I know the upper control arm was changed but It still has the 72 Lower. if I do buy it for a 73 will it bolt to my 72 lower arm?