I need a replacement for the module in my 93 Chevy K3500, 7.L, 480LE, 4WD pickup. It had pn 16158995 QWD DRAC in it, are all the QWD modules interchangeable, or do I need the exact pn? The tech working on my truck said the part had been superseded several times but he didn't know what other pn's might work.