Are the 81/82 and 83/84 250R frames similar? CR480 exhaust

[TheRealFatShady]

I found a pipe from a CR 480 'modified to fit an ATC 83/83 250r chassis'.

Will it likely fit my 82 250R without much modification, or were the pipes entirely different for those years in terms of how it was routed through the frame?

Thanks

[RodKnockRacing]

I know the 81 82 frames are completely different than 83 84