Question about mix/matching GT-FOUR parts

[angryface]

Hey guys, I'm doing a GT4 conversion on my Mazdaspeed Familia GT-R, this has been done before. It's known that the ST205 is the strongest and most refined of the GT4 drivelines, so if I can use those parts I will. It's economical for me to purchase a ST205 rear end from Japland, but shipping costs equal that of the transmission, so I'd prefer to buy one locally. The ST205 Celicas weren't available in Canada, but the ST185s were, and I managed to find a couple of transmission locally.

The question: Can I use a ST185 front-end with a ST205 rear-end, using either a ST185 or ST205 propshaft? If not, what would be the issue preventing that? Gearing, length of propshaft, something else? Thanks