How many supplies did Liu Bei have at Dangyang?
Yes, 兩 used to have many more meanings.
In the details section of zdic, there's the following additional meanings:

(4) 匹(长四丈)
归夫人鱼轩,重锦三十两。——《左传·闵公二年》
(5) 通“辆”。车一乘 [used for buses,carts,etc.]
武王戎车三百两。——《书·牧誓·序》
之子于归,百两御之。——《诗·召南·鹊巢》

Definition 4 shows that it's also a measure word for silk fabric, but in this context definition 5 would be more appropriate - it is indeed the same as the modern 辆. So &quot;輜重數千兩&quot; should mean &quot;supplies of thousands of carts&quot;.