If you go to http://www.ingersolltractors.com and then click on the "illustrated parts list" link near the top of the page, you can scroll down the list of PDF's to the tractors and then click on the one for the 442's. When it opens for you, scroll down until you get to pages 76/77 of the actual catalogue or page 40 of the PDF.
There you will find an illustration of the sleeve hitches for both the 200 and the 400 series tractors. The long arm which is item 2, is the one that connects the sleeve hitch to item 8, which is the bracket that bolts onto the bellcrank of your tractor. The bellcrank is the item that moves back and forth on the right side of your tractor (and the left too) that lifts up your mower deck whenever you pull the lever on the right side of the steering wheel.
I don't know of files here but in the Yahoo group there are files with lots of building info for sleeve hitches.And I think that is where the info in one of the above post came from.
Bart knows alot about the what to's of these hiches.As does other guys also.
I was thinking of building one.I no master fab guy but I have built my own full suspension single seat 250 powered buggy.I have my own mig. and stick welder, tube bender,metal band saw along with most other shop type tools. I post pics.of the buggy later.Thanks I'll check out the other site see what prints they have.