Anythings possible and I'm no 250R expert at all, but I believe the chain is on the opposite side on the air cooled from the liquid.
Also the air cooled has a shock linkage and mounting setup that keeps the shock low and almost horizontal. The liquid coolers have the shock closer to verticle.
You never know until you try.
1986 Tecate
1984 Tecate
1985 Tri-Z
1986 ATC350X
1985 ATC250R (2)
1985 ATC125M (2)
1982 ATC70 - Original Owner
175 TriMoto Frame with Pro-Tec Rear Suspension
3-Wheelin' since '82