T-850 transmission question
 

I am looking for a 5 speed T-850 transmission that was in a delivery truck made in mexico and europe. the input shaft is 21splines does anyone have any info for me. i know this is vauge but its for a project i am working on for my srt-4. Neon T-850 transmissions are garabe. input shaft isn't rated but to 300whp if that. If i can get a custom disc for my twin disc setup i would be able to run this input shaft.