The issue is depth, specifically from the back of the ring to the front of the timing-chain cover.

A stock balancer for a '94 Mustang 302 is 4" deep from front (where the pulley bolts to) to back
(at the timing chain gear), from what I measured on a stock balancer. What I didn't do is measure
the depth on a stock balancer from ring to TC cover. If I had to guess from memory, there is about
3/4-1" space max.

I bought an ATI Balancer part# 918929 but when I put it on, there is about a 2" gap between the
back of the ring and TC Cover. This balancer is also 4" from front to back. The ring itself seems a
little narrower than a stock balancer ring but I don't think it makes up the difference.

I pulled the TC Cover off to make sure the new balancer is seating all the way and it is. I'm at a
loss.

Any ideas?