[Synchro909]

Here's the method I use:
Remove spark plugs
Jack RH rear wheel just clear of the ground and mark the tyre at 12 O'Clock ( I use a spirit level to get it as close as I can)
Set the hand brake so it is just dragging
Select 3rd gear and direct drive if you have an overdrive
Turn the engine exactly 2 turns.
Now, if the mark on the tyre stops at 11-12 O'clock, you have 4.11
12-1 O'clock, you have 3.78
1-2 O'clock, you have 3.54