I typed a long response around lunch time before I went to work, but the forum did a hiccup and it got deleted. Any way, what you say you know is actually incorrect and just not a good identifier of the difference between an M60A1 RISE/Passive and an M60A3TTS.
The RISE/Passive (I'll call it an "A1" for short), had a fairly long life in the Regular Army, Army Reserves, Army National Guard and Marine Corps. By the time the Guard and Marines were done with it, they had top loading air cleaners, passive sight for the driver and cupola, later tracks, a mix of either road wheels, M240 coax, smoke grenade launchers, and grenade stowage boxes.
I have both AFV Club kits as well as being a former M60A3TTS crewman. The only real external differences between an "A1" and "A3" are few. The A3 will have a thermal shroud. It will have a laser range finder in the right blister. It will have a crosswind sensor mount (the actual sensor rarely worked and was kept inside the turret). It will have the enlarged gunner's primary sight housing (aka "doghouse") for the tank thermal sight (TTS). The search light power port will be molded over. These are differences between a manufactured A1 and a manufactured A3. Some foreign countries bought packages to upgrade their A1s to A3s so there can be fewer differences.
I'd have to look at my AFV kits to give real specific part numbers, but it would be easier to back date the AFV A3 kit into a late A1 than to update the A1 into an A3.
- To get a USMC late M60A1 RISE/Passive (without ERA) from the M60A3 kit just use a non-LRF right turret blister (or drill out a hotdog shaped hole in it).
- Use a plain 105mm gun tube. Many aluminum ones to chose from.
- Omit the crosswind sensor mast.
- Use the searchlight power connector the kit includes.
- Use a smaller non-TTS doghouse. I think the way the Tamiya kit is molded is with the original doghouse in place and the enlarged TTS housing glued over it. Not sure about the AFV kit without looking at the sprues.
My M60A3TTS in 1987-89 had a mix of steel and aluminum road wheels. It was manufactured with aluminum ones and once the type changed, replaced with steel ones as they wore out or were damaged. The only rule was that both road wheels on one arm had to be the same style. So you couldn't have an inner aluminum one and a steel outer one on the same arm. On an A1, you could use one or the other or intermix them.
As late as 1988-89, we were given technical manuals on how to mount the ERA on our tanks before the decision to upgrade us to M1A1 tanks.