Older New Model Army conversion question

[Ala. Bushwhacker]

Hello,

I have a question that has been likely asked before (but I can't find an answer by searching). How will a conversion cylinder like Taylor's fit in a Pietta New Model Army (1858) made in the mid 70s?  Are there much differences in sizes in the older reproduction revolvers and those more current? Thank you for any help that you can provide.