TR-3A keys and locks question

[John Cowan <jfcowan@sj.znet.com>]

Saw a thread about TR-6 key assignments and have same question about my '60
TR-3A.  Presently, keys are as follows:

Ignition:     Round, Yes (easy)  Square, Yes (difficult)
Doors:       Round, Yes             Square, No
Trunk:        Round: No               Square, Yes
Glove box: Round, ???             Square, Yes

Glovebox question mark means I rashly had it rekeyed without thinking the
problem through.  Subliminal memory suggests I used circular key in
ignition years ago, but am using square one now.

Two questions:

1. How is yours organized?
2. Why would both keys work on my ignition?

Thanks

John Cowan