Back to 2 piece driveshaft

[72chevyLWB]

I had nothing but problems with my 1pc. I originally paid $20 for it. It was fine last year, but this year I had it shortened for the 700R4. That cost me $80 with a new yoke. Then it started vibrating a little. All of a sudden my spring perches snap and send the driveshaft into a crossmember and bend the hell out of it. So $20 and I had a guy weld on a new end ( he said it would be fine) the I get it back from him as he said it is perfectly straight. I get it on the truck and it wobbles like a mo-fo. So I take it off and have another place weld in a new pipe. $60later and I have two driveshaft ends and a 1/4" thick 2.5" steel pipe connecting them. The thing weighed 50lbs. So I put that on and still had a vibration. Well the vibration ended up loosening the pinion nut and stuck the pinion into the carrier ( guess what sound that makes). So I had to trailer the truck home and fix the rear end. I put the shaft back on and it still had vibration, so in the garbage it goes. I went to a junk yard and got a 2 piece from an 86 chevy. I had to get the front lengthened 4" to put it on. I ran it up to 100 mph (with no rear shaft) and there is no vibration at all in it. The place was supposed to have the rear done on Friday (lengthen 8") but they never got it done and here I sit bored out of my mind.