Can anyone tell me how they modified thier parking brake cables after they swapped over to a TH200-4R?

What are you referring to by "modified"?

Do you mean relocated - is there interference between the transmission and the cable routing?

Are you talking about when you move the cross member back, You need to shorten the "S" hook?

I guess I should have phrased the question as, Do I have to modify my new e-brake cable kit for my old powerglide to fit the mods I had to make for my 200-4R? Moving the crossmember back 6 inches.