I bought a d6 cat about a year ago and snapped some pictures of it. It took me a while to find out what year it was because people kept telling me the serial number was in the cab. Turns out it was under the magneto for the pony motor. This is a 1953 D69U. Serial number is 9U140XX.

Lauren drives the Cat Brettyn drives the Cat Side view Back view Engine Right side Engine Left side

I bought a Operator's Instructions manual for my cat. It appears to be a bit earlier than the original (there is what appears to be a date of 1-48 in the back). It's labeled form 10493A.

Here are some pictures from the 2003 steam-up at antique powerlands in brooks, OR.

Cat Line-Up - Cat 10, D2, D4 Cat Sixty Cat D9 Holt/Cat 75 Holt/Cat 75
Case Steam Engine Case Steam Engine, Holt Cat in background Russell Steam Engine Russell Steam Engine

Here are some more steam pictures from the Henry Ford Museum in Dearborn, MI

Gothic Beam Steam Engine Model Steam Engines Beam Steam Engine Steam car

Here from Brighton, MI a nice example of a Hi-Track. This can serve as reference for the long discussions on ACMOC regarding ease of maintenance versus productivity. I think it illustrates the trade-offs well :^)

Big Cat

Here are some links I've found. Not much out there. I haven't bought anything from any of these folks either so please don't take this as an endorsement. ACMOC has a bulletin board. Dene has a great D2 page.

Guy in Oregon selling old crawlers
General Gear
Yesterday's Tractors
IBDozing
ACMOC
Portland, OR CAT dealer
NW US/Canada antique equipment for sale
Cat seat cushions
Dene's Crawler page
Zenith Fuel Systems - Manufacturers of carbs for the pony motor
Magneto parts

Here are some tractor places in Oregon I have heard about - no personal exp. to date.