A stock 742 case sure grip is becoming hard to find special parts for. NO new spider gears are available, (Roy, SGBARRACUDA (RIP), built my 742 and spent a long while looking for spiders. He finally found one used). The clutches can be had from Dr Diff for a 9 1/4 that requires slight modification .to work in a 742. 8 3/4
I would go with the power lock
