relative pronouns - How can I diagram the direct object placement in "... the watch that my uncle had given me."

Please consider:
"... the watch that my uncle had given me."

• "my uncle" is the subject.


• "had given" is the main verb (past perfect).

so...

• "me" is an indirect object? or should it really be "had given to me" ? Either is ok, I think.


• "that" is a relative pronoun? the antecedent is "the watch" ?


• "the watch / (that)" must be the direct object of "had given" , so how can it precede "had given" ? Given the English sentence structure rules that I am aware of, I've no clue how to explain the placement of the direct object.

I'm a native speaker who teaches my friends by using sentence diagraming. I need some help. thanks.

addendum:
sorry. I should not have called " has given " the "main" verb. full sentence:

(full sentence): "I lost the watch that my uncle had given me."
(1) "me" does not effect the grammar, so I'll drop it.
(2) "that" sounds like a conjunction (not a relative pronoun), and it is natural in English to drop "that" when it is a conjunction. This does not change the grammar.

(stripped down sentence) "I lost the watch my uncle had given."

1. can "watch" really be the direct object of two verb???


2. or, is "that" really a relative pronoun. If so, then "that" can be the direct object of "had given" and "watch" can be the direct object of "lost" . Further, dropping "that" , even though it sounds natural, creates an incorrect grammatical structure.