drive shaft lenght

My local shop only charged $120 to lengthen my driveshaft when I switched to a manual. I'd recommend a small local shop for a better price. (I know, too late now)
Ya… local shop was an hour away and they did a great job and did exactly what I wanted… however… I was wrong… and that’s where we are now, and chasing a driveline vibration when everything is new/rebuilt from flex plate to rear tire… and the vibration was there before I started this project. So this time I just opted to include no part of the old driveshaft or slip yoke, and start fresh with correct measurements for correct length, and see what that got me.
This is the kind of thing that can and will screw with your enjoyment of the car later. I took it to a local show this past weekend to show and by the time I got there I parked it in the visiting lot as I was 100% over it after a 20 minute drive…. Did not want to even talk about it… but I still did cause well, it was frustrating. Not to hijack but hoping me sharing my experiences with my build and what I would/am doing different now that it’s actually drivable and scary at speed I want to enjoy… measure for custom fit using all new parts and cross that off the list of places to chase later….