got engine to fit,not too hard all mounts line up front mount hard mounts as rubbers in frame on mc18,top crankcase mount lines up just needs a spacer on each side,rear lower mount needed to file small amount off case and frame crossmember to clear ,as case is slightly larger to accommodate rubber mounts.no need for inserts in cases,hard mount at front others rubber as was in mc 18. any one got mk1 mc 18 swingarm and wheel spindle,needed to complete rolling chassis. going for 1988 rs250 look. cheers