I pulled a 30 or 32 inch Parker sweeper for many years, was fine on our 3/10ths acre lot with about 5-6 trees, but was a huge amount of time spent covering the 2-3/10ths acre lot we have now. Similar to you, had a cart I made sides and top for, had a spare K-161 engine, has implement attaching points on back of my #72. I tried to pattern the blower after an IH #56 or #60 silage blower. Didn't really work that well. Patterned it more after a Trac-Vac but semi-mounted the blower so the pivot point of the hitch was as close as possible exactly between the rear tractor wheels and the cart wheels. The blower worked much better feeding into the center of the housing and exiting out the top. My cart was 32 inches wide, 42 inches long, and sides and existing cart is 36 inches tall. 28 cubic feet, and I can fill it all except for a very small space right inside the cart from the discharge hose. Pulling it while filling it REALLY packs it the stuff in there. I use a spare pto clutch off a narrow frame to run it and turn it off/on. I bought a 3.50x4 tire & wheel from Northern to carry the engine and blower, milling the keyway on the 1 inch blower shaft was a government job at work, boring the slug of steel that is the hub of the blower was also a Gov't job, boring a 1.00" hole 6 inches long with 3/16" jetway is beyond my tools capability. Work did that all day every day, took a half hour. Bought two face mount 1" pillowblock flange mount bearings. EVERYTHING else was made from flat steel sheet and plate plus some angle iron I bought. I hauled about 500# of steel home one Friday night. Took me a year to get it the way I wanted it to work. When it got so I was getting 25-30 loads of leaves/clippings I just mulch them on a windy day and let the wind carry them off. I easily have twice the leaves now that I had in 1997 when I built the vac. A new Trac-Vac was about $2600 back then. I have about $800-$900 in mine including rebuilding the K181 Kohler. I ran the thing from about Noon on Fridaytill 2 AM Saturday morning... non-stop. Took Saturday off, then aerated my whole yard twice Sunday, once N&S, once E&W. Put 25 hours on the #72 and about 30 gallons of gas thru it just that weekend.