I did the double row chain on my '77 R100/7 without much trouble. My sprockets were in good shape, I didn't want to remove them (and I didn't have any pullers). So I cut the chain with a cutting wheel and installed the new chain and master link. I did replace the tensioner assy... I didn't have any real trouble. I have put about 10k miles on it since...
I'm on bike bike number 20 something, I think I lost count. '77 R100/7