Tractor, Crawler, Diesel, 70 to 90-DBHP, Standard, Caterpillar D7, 74-In. Gage, with La Plant-Choate R-71, Angledozer and Le Tourneau R-7, Power Control Unit. Serial Nos. … Civil war carbines from service to sentiment / A.F. Lustyik Tractor, Crawler, Diesel, 70 to 90-DBHP, Standard, Caterpillar D7, 74-In. Gage, with La Plant-Choate R-76R, Angledozer and Le Tourneau R-7, Power Control Unit. (Serial Nos. …