I need to repair a Pearl Grandfather clock

by Randy Veach
(Round Rock, Tx)

I purchased a pearl grandfather clock 34 years ago for my wife's birthday. It still works, but has some issues. I need to replace the movement, and have a few questions.

The book shows the movements as; H-451 / H-461 / H-1151 / H-1161. How can I tell which movement I need?

E-bay shows a Hermle 451 050 HS for sale, is that the same as the Pearl H-451?

E-bay also show different cm (94, 114), what is that about? And how can I determine which one I need?

Replacing the movement looks pretty straight forward. Am I over simplifying the change?

Is there anything I am overlooking?

Thanks in advance for the help.