Carefully read the first post here, including the documentation linked, then decide if you want to do it, or who you want to let do it. Propshaft Rebuild
Personally, I'd only let a driveline shop do it, if I didn't know how or want to tackle it.
Antichrist and DM x2 on that - the shop is no good. the double cardan is not unusual, my 76 cadillac deville has one on each end of the shaft. These things have been around for a long time and any competent shop can do it for you.
just fyi the caddy shaft is twice the size of the landys shaft, it has the 501 cubic inch engine (8.2L) and about 600 ft lbs of torque (bugger all horse power but lots of grunt).
X2 on that. I rebuilt my driveshaft but the center ball was chattering so I'm definitely buying the Tom woods one. It's not too bad just don't drop you ujoint and spill the bearings everywhere like I did
Went out to try and take off my drive shaft. Not surprisingly, the bolts are on really tight and I can't fit a socket in to get them off. Plus, some of the bolts are out of reach on the top side. Any tricks to getting a socket or wrench on the bolts and getting this thing off?
Soak the fasteners in a 50:50 ATF/Acetone mix to disolve any rust.
If you have CDL put one wheel on a jack stand and lock the transfer case.
Use a 6pt box end wrench (or at least a flare nut wrench) on the nuts. You'll have to use an open end on the bolt heads.
Once you have the ones you can access loose, put the tranfer case in neutral and rotate the shaft to get to the others, then put the transfer case back in gear.
FWIW, I had my front driveshaft rebuilt by the shop recommended by a local mechanic. When installed their was a weird high pitched noise, the shop investigated and it turned out to be some paint overspray on the ball joint. The costs/hassles of uninstalling and correcting the issue were transparent to me as it in, fixed, and out fast and without cost to me.
Overall, I'm really glad I went with the shop that the local mechanic had worked with and trusted. If I had brought a driveshaft in and the same thing had happened--I'm paying for it, plain and simple.
Also, the driveshaft seemed to be rebuilt to a high standard and it's running well for me. All wins!