1974 GMC Sprint 454

I have a 1974 GMC Sprint with a big block 454. needs some floor pan work, some electrical repairs, carpet and seat cover needed, and transmission not working right. Truck ran but now does needs the transmission rebuilt or replaced.I was cleaning up the Sprint today 9/20/2020 and started having transmission issues (not shifting when warmed up). Truck is being sold as is.I'll do my best to troubleshoot transmission mean while. Starting bid has been lowered to $4,400. Thank you and happy bidding.Iwas cleaning up the Sprint today 9/20/2020 and started having transmission issues.Truck is being sold as is.Thank you and happy bidding.SEE VIDEO LINK BELOW and that's how it ran before 9/20/2020 https://www.youtube.com/watch?v=iXJ3WqEiHCo