Aftermarket bell housing length

Replacing my c6 with c4 measured the length of my c4 with the factory bell housing to get approx driveshaft length then got to thinking does the aftermarket bell housings lengthen or shorten the overall length of the c4. Jw 460 bell is the new that I have been looking at buying

The one I delt with was about .200 shorter and required two block plates to barely work. Stock 400 bell had plenty of endplay.