M110 Front Crankshaft Seal Spacers
 

There's some really excellent posts on installing the seal.
The seal I.D. rests on the Spacer Ring, but for the M110 I'm working on now, there's a big distance between where the Seal seats in block & the Timing Chain Sprocket, allowing the Spacer Ring to probably wonder in between both along the crankshaft. Do I need to install an extra spacer to keep a Spacer Ring positioned inside the Crank Seal? I would think my present setup would let the Spacer move towards the Timing Chain Sprocket & loose contact with the Seals I.D.
Some Crankshaft Seals have a full outer flange, some with 1/2 a flange 7 some with none. Wouldn't the Seal with the full flange be preferred?

are u sure???