You're right it would still be a string which is easily converted. To handle a variable number of spaces, here is a change node example using JSONata:
rule 1 changes multiple spaces to one space
rule 2 splits the string into an array of three items (no spaces)
rule 3 grabs the second item in the array (the string characters of the number)
rule 4 converts it to a number
Here is the flow and with will handle decimal points in the number too
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