Car on the lift, suspension bottomed-out, but seems like the spline joint is out waay too much (pic below), especially there are sighns of the "other position" previously, as if it was entering the transmission more, based on the marks on the splined pipe (freshly polished, polished previuosly, untouched just before U-joint). Is it ok as is, or does it stick too much from tranny?
Possible reason for the difference is: the LT1 car was initially '94, but got a '97 body from a 3,8 car. I'm not sure if transmission and driveshaft are from '94 or '97 car. Where could be the difference coming from? Are the driveshafts same for '94 5,7 and '97 3,8? It vibrates a bit on high speeds, nothing noticeable up to ~80 mph.
Thanks for your ideas!

 

looks ok to me, v6 transmission will not fit on a lt1. you may have v6 differential which is not normally a posi trac and usually has 223 gears. do you have stock style trans mount or is it aftermarket poly?

 

LSD is in place. And I'm rather at 27X final gear, as per rpm at 75.
Thank you for the opinion. Very pleasing to know, v6 tranny is not in the game