Where front and equipment mounting frame, etc., is specified, furnish combination forward tilting butterfly type hood or equivalent construction. 2.3.2 Conventional Units - Engine ahead of cab. 2.3.3 Tilt Cab Unit - Engine in, under or to rear of cab. Cab easily tilted or elevated to permit easy and complete access to engine. Secure, foolproof hold down lock on cab. Cab removable through use of springs, power, or other work saving means. Cab overall width at least 66 inches. 2.3.4 Forward Control Unit - Engine next to or behind operator's seat. Operator's seat elevated for step-in, step-out use. 2.3.5 Compact Unit - Engine next to conventional type operator's seat. 2.3.6 Five Man Cab Unit - Conventional type with sedan type cab, 3 or 4 doors with at least 2 doors on curb side...