Mandarin equivalent of 後尾 (in the end)?
广州话普通话 defines 後尾 as

粵
表示時間或空間上居後

with two sample sentences

佢後尾卒之簽咗字
他最後終於還是簽字了



佢排隊排到最後尾。
他排隊排到最末尾。

广州话方言词典 starts of with pronunciation

hau6 mei5

and it has the first definition:

1 後來；最後

with one example sentence in Cantonese and Mandarin

佢後尾點樣ǜ？
他後來怎樣了？


and one Cantonese example:

後尾大家都同意。

definition two:

2 末尾；最後（指位置）

and one example sentence:

最後尾樖係李樹。
最末尾的那棵是李樹。

it also lists pronuncation:

hau1 mei1

and defines it as:

後來；最後；後面

with two sample sentences in Cantonese and Mandarin:

佢後尾點呀？
他後來怎麼樣了？



你高, 企後尾啦。
你高, 站在後面吧。

Depending on the context you could choose something like 最后、末尾、后来、后面.