Haven't heard it said yet and it may be obvious to some but this tip had
me grinning.

 I used slotted area washers similar to a fender washer to minimize
effort in engine sag adjustment.  Initially, I built my engine about a
1/4" low with two slotted washers on the top two mounts.  After a little
sag they are easily removed without having to pull the bolts.
Subsequent to a little more sag they are semi-easily installed on the
bottom two mounts.  You'll still have to remove the nut to add a
compensating washer but at least you won't have to pull the bolt.

Larry Henney
360LH