Tommy Stickle

Can anyone help me find cab corners and rocker panels for my 1980 Mack i beleive its a r model but the only thing i find is up to 1976...Its a day cab tractor that was turned into a single axle dump..... Is there anyway i can retro fit the early r model cab corners to my truck...I have a english wheel and planishing hammer but that really seems like alot of work for a daily driver....any info would be great....Thanks