I guess Andy beat me to it. Oh well, here is more info, for what it's worth.I would not recommend using the M1A2 SEP kit. There is more work reworking the rear to an M1A1 than using the Tamiya kit or the Dragon IAM. The tracks are not an issue, either the T158 (AIM kit) or T158LL (in the SEP kit) tracks are correct for a current M1A1 AIM.
Legend used to do a Bustle Rack APU in resin. You would still need to correct the sight box, I don't know of any repleacement for it.
Some USMC (and Army) tanks did not have the APU in the initial phases of Iraq. The Echelon sheets show which versions were without them.
Here are all the mods you would need to do to bring it up to the same level as the Dragon AIM. Its up to you on how much you want to do on it.
US Army M1A1HC/AIM/A2 UpgradesThese are upgrades to bring the older Abrams kits up to the latest standards. Not all of the upgrades are on all tanks, you will have to check your references on the one you are building to see which upgrades/modifications it has applied to it.
EPLRS antenna mount, thin post to the right side of regular antenna.

BFT antenna (w/ GPS antenna on it) attached to gunner's doghouse.


You will not usually see both the EPLRS antenna and a BFT antenna installed on the same tank. It is usually one or the other. The EPLRS antenna mounting post will still be present when the BFT antenna is used, just with a blanking plate on it as opposed to an antenna base.
APU Power Junction box. New electrical conduit is the angle-iron piece running along the left side of the blow-out panel.

Power connection box next to the man-hole cover. There are two screw caps to connect to located on the front of the connector, toward the front of the tank.

PLGR antenna mounted somewhere on the turret roof. It is usually in front of the crosswind sensor. I have also seen it to the front right of the TC's cupola, or on the BFT antenna, as shown above. The location for it varies.

PLGR antenna on M1A2

Tank/Infantry Phone and rear Slave Cable Receptacle on right rear of hull on latest AIM tanks. These were not present until about 2006 or so.

Deep fording kit exhaust flange on HCs and AIMs.

Forward MCB power/control box connector next to driver's hatch. This feature also is a later one as part of the AIM rebulid and was not seen about '06.

Check
Prime Portal for more M1A1 and M1A2 pics.
Check out my
M1 Variants Article as well for more info and pics.
USMC M1A1HC/AIM UpgradesChange out the smoke launchers to the USMC 8-shot, double-stacked type.


BFT antenna (w/ GPS antenna on it) attached to gunner's doghouse.


You will not usually see both the EPLRS antenna and a BFT antenna installed on the same tank. It is usually one or the other. The EPLRS antenna mounting post will still be present when the BFT antenna is used, just with a blanking plate on it as opposed to an antenna base.
APU Power Junction box. New electrical conduit is the angle-iron piece running along the left side of the blow-out panel.
Power connection box next to the man-hole cover. There are two screw caps to connect to located on the front of the connector, toward the front of the tank.
PLGR antenna is mounted somewhere on the turret roof. It is usually in front of the crosswind sensor. I have also seen it to the front right of the TC's cupola as well. The location for it varies.


Tank/Infantry Phone and rear Slave Cable Receptacle on right rear of hull on latest AIM tanks. (Added in '07. Prior to this, they had just the T/I box on the right rear.)

Deep fording kit exhaust flange on HCs and AIMs.

The box in front of the loader's hatch is an MCD (Missile Countermeasure Device). It is used to defeat optically and laser guided anti-tank missiles.


Some USMC M1A1HCs are using the old sprocket retaining rings as well. They were found to be an easy fix to counter the track losing tension during operations. The USMC started putting the rings back on M1A1HCs in the early-mid nineties that were stationed stateside on the West Coast (1st Tank Bn) and they were seen on tanks on deployment with the MEUs until 2006. No rings are/were on the sprockets of East Coast (2nd Tank BN) tanks though. Most USMC tanks that came off of the Maritime Preposition Ships (MPS) in Kuwait for OIF I /II did not have the sprocket retaining rings, other than at least three known tanks that came off the MPS ships with them. The USMC tanks that have been seen in Iraq with retaining rings are from stateside (1st Tank Bn). They are part of the different ocean-going Marine Expeditionary Units (MEU) that have gone to Iraq and participated in the festivities over the past few years. So, specific USMC tanks could be seen with the rings applied.
The below pic is a USMC M1A1HC in ops in Kuwait with the rings on it.

For the USMC BRE used in OIF.
Eduard makes one in PE, set # 35598. There is also one in the new(ish) Academy M1A1 Iraq 2003 kit. It is one of the few good pieces off the new J sprue. It also has a T/I Phone box on the new sprue. The rest of the kit sucks though. The Dragon M1A2 SEP kit comes with a nice PE and plastic one as well.
You can take a look at my
M1 Variants Article as well for more info and pics.
You can also take a look at my USMC M1A1HC that I did a while ago.
"Angry American", USMC M1A1HCThe Tamiya M1A1/A2 kit comes with the MCD and smoke launchers. The Academy kit also includes the T/I phone box, smoke launchers and MCD as well. Echelon makes a couple great decal sheets for Marine Abrams in Iraq too. They also have another sheet coming out soon.
You can take a look at my
M1 Variants Article as well for more info and pics.