There shouldn't be a difference between 2seater & 2+2 T5's.... I have a T5 from both and I know they have the same output splines because I've interchanged them.
Do you need a 2seater or 2+2 length driveshaft? On my original turbo project my donor was a 2seater, my car was a 2+2... I took the driveshaft to a local driveshaft shop, and for $100 they lengthened & balanced it for me. Took less than 24 hours too.