What do you mean? Are you saying you want to put the 85 rear end on your red or put a whole shock system on? I was planning on doing this a while ago and have plans that I drew up. I eventually figured that i might aswell sell my 200 and get a 250 beacause the work involved is alot. You will also need a trx 200 84' to get parts off as they have rear suspension on them. Let me know if you need anymore help.
Matt
1980 ATC 70 Needs Restoration
1985 ATC 250es Fully Refurbed
1986 ATC 350x Mint Original