Ukraine’s 4th Tank Brigade Has A Frankenstein’s Monster T-72 That Mixes And Matches Parts From...

Normal SOP for militaries even ours. We had to manufacture pre-amps in our shop to keep our IFF's on the air. When we ran out of parts we kept them on the air with an unauthorized modification. It worked wonderfully

We didn't (quite) do that with tanks, but the M48A3 tanks sent to Vietnam were certainly not-all-the-same and some were assembled from mismatched parts. No M48A3 (or later M48A5) tanks were ever manufactured by the tank plant, instead ALL M48A3 tanks were assembled by the Anniston Army Depot using turrets and hulls from various models of earlier M48 tanks. The job was done on contract so only the specific items listed in the contract were changed. All the M48A3 tanks got the diesel engine and the matching air cleaners. They all got the M17 rangefinder. Later production M48A3's all got heavy steel boxes around the tail light assemblies. Later M48A3 tanks also got a ring of new large vision blocks added between the turret and the cupola. If the hull was an early M48 or M48A1 with the tension roller between the rear road wheel and the sprocket, that was cut off, if the hull came with three support rollers on each side, then that's what was on the finished M48A3, but if the hull came with five support rollers on each side, those all stayed.

Later when the Army needed more tanks, the left over M48A3 tanks were converted to M48A5 by replacing the 90mm main gun with a 105mm gun and updating the sights and fire control, but nothing was done to the hulls beyond routine repairs of any damaged parts. So again the M48A5 might have 3 support rollers or 5 support rollers, and might have either style headlights.

Just to make it a bit more complicated, some M48A5 tanks kept the cupola and extra vision blocks while other M48A5 tanks had the vision blocks and cupola removed and a low profile commander's hatch with external weapon station installed.

Nearly all the M48A5 tanks went to the National Guard. At one point NGB decided they wanted to fund an extra week of training for new NG tankers to teach them about the M48A5 because all tankers were being trained on the M60A1. This yielded a strange back and forth discussion between NGB and the training brigade over what would be taught. NGB kept saying they wanted the training brigade to "teach the differences between the M60A1 and the M48A5" while the brigade kept asking "WHICH differences?" That debacle reached the point where NGB sent an officer to Fort Knox to show us "which differences" -- we parked one M60A1 and four M48A5 tanks together in the motor pool. Every time the NGB officer pointed out a difference, we would show him that some of the M48A5 tanks didn't have the same difference. Eventually the brigade and NGB agreed to just give the NG tankers a week ON the M48A5 so they could see that the differences didn't really change anything.