I have an old Holt crawler (pre CAT) that had a Model A engine and transmission attached (or so I believe), including the Ford blue hood with radiator! I fired it up once just fun, and it was just that, damn funny! The Holt controls still declutched the tracks, and the steering wheel that as added ran to a steering box that actually raised and lowered the homemade wooden blade! It stills sits out in the yard, if anyone is interested, I could post some photos.