[Legbreaker]

Found this:

The XLF 40 based on the X1. 3 cochetes 40 Avibrás 65km range.

And this:

The X1A2 was the most powerful and the most modern of all modifications, modernizations and adaptations of the vehicle tank light M3.
To an observer who does not know the evolution of the vehicle, its origin probably unnoticed. The X1A2 is the result of a process of evolution which of course has its origin in the M3 light tanks supplied by the United States to Brazil after World War II. in 1973, the first modernized version of the M-3, which went on from there to be known as X- 1, which was approved and was followed by the modernization of 80 units of M-3 Stuart X1: the first modernized version of Stuart in Brazil. 80 of them were converted X-1 has been improved its ballistic characteristics, with more pronounced side plates more resistant steel. The gasoline engine was replaced by a Scania DSII engine manufactured in Brazil, with 260cv power six - cylinder (which gave the vehicle a number four times higher). The change is also felt in replacing the turret of origin with a cannon 37 mm with a new, equipped with a 90mm cannon DEFA mod.E2F1 French. it was also modernized communications system. the X1-A1 is similar to the previous version, but it is clearly identified by the existence of three ' boogies' six wheels instead of 2 'boogies' with four wheels that characterize the standard model. This vehicle did not enter service. The knowledge resulting from this modification, Bernardini went on to the next phase of the X1-A1. The "new" X1-A1, she underwent a radical change when a third boogie, four was added to six lateral support wheels. This change resulted in the need to increase the length of the vehicle (150 cm), which now has more than 6 feet long. However, this "new version" worked only as a prototype and was never approved because it is considered that the changes were not sufficient to justify the investment. X1-A2 - the last M3 the X1-A2, it was virtually rebuilt and only remember the vehicle that caused it . The allteração in front of the vehicle, is a telling example of the changes. With several suggestions from the Brazilian army, then still in the 80s, and based on the model X1-X1 A1-A2 "stretched". This new vehicle changes very significant, which means that anyone looking for him hardly find their origins in the old M3 Stuart. with the completely revised framework, especially in the front, which completely altered the look of the car, the X1-A2 maintained suspension system shown in the X1-A1 and the engine was revised prototype, gives power 280cv. a turret modification with a 90mm cannon manufactured by Engesa equal to the tanks light was included snake rattlesnake. With this amendment, the X1-A2 could fire armor - piercing ammunition modern (arrow). However, it did not include any electronic observation since its function will remain the vehicle secondary support. The fact that it is a concept 30 years, heavily modified, has led many vehicles were unchanged, at a time when the Brazilian industry was already able to make changes not only in the most powerful tanks as he was able to design and produce. therefore, the main advantage of modernization projects M3-A1 / X1-A2 had to do with the creation technicians who were trained not only to make such modifications as the project root of new armored vehicles. The modernization of the M-41 Brazil was one of the consequences and the creation of armored vehicles and Tamoyo charrua as were others. Tank Tamoyo Charrua

Also another picture from a different angle
Attachment 3683
And:

Developed in 1976 by ​​IPD - Institute for Research and Development Army, in conjunction with Bernardini, Avibrás and other companies. It was only this single prototype. Use the base of the X1. It
took 3 Avibrás 40 rockets with a range of 65 km. Each rocket weighs 550 kg.