[neverdem]

The only thing heavier is main battle tanks, and I don't recall seeing any M60s or M1s at the Waco standoff, do you?

I wasn't a tanker, but I worked around them. The lead vehicle appears to be a M60 variant. IIRC, the one on film at Waco had a boom as it started to bash the walls of the burning compound. My guess is that it was an engineer variant or armored recovery vehicle. The first two tracked armored vehicles appear to have pronounced turrets from the rear in this picture.

[Spktyr]

I don't think they actually had their main guns mounted, which makes them an odd variant of their own. Put it to you this way - I didn't see any intact MBTs in footage or pictures of the Krispy Kritters incident. I did see the M88 and the engineer variant of the M60, though (can't remember the designation offhand).

[Oztrich Boy]

They also had a couple of M1A1s