The mounts on the left are for 2WD models. The
mounts on the right are for 4x4 trucks. Notice the slotted mounting holes, which
allow adjusting the motor position rearward by up to 1-3/8" and side-to-side
by up to 1/2" so that you can position the engine exactly where you want
it. The two sets of "slots" on the ears are because the 2WD Blazers have
different mounting requirements than the 2WD trucks.
These mounts are designed
to be used with the stock S-10 2.8 V-6 mounts, and are made of 1/4" mild
steel, except for the base plate on the passenger's side mount, which is 5/16"
thick. Some companies use thicker steel or gusset the mounts, but this causes
problems when tightening the mounting bolts, because the "ears" on the
mount will not pull in easily and clamp properly.
The mounts offset the
engine to the passenger's side to improve steering shaft/exhaust manifold
clearance. On the 4x4 models, offsetting the engine allows using the offset oil
filter adapter, instead of a remote oil filter.
For those who want to make the mounts themselves, the drawings of the motor
mounts are in the Chevrolet
S-10 Truck V-8 Conversion Manual.
Better V-8 Conversion from a Better Motor Mount Design—