Sonny - Thanks for looking

Bunk you are correct. ARPS is now owned by Ameriquip.com. They also still make other (an assumption) farm and construction pieces. I believe they private brand B/Hs for the smaller tractor manuf. Lots of B/H pdfs there. One of the pictures on the net has a RL-24 caption with an add'l 708. The 708 is listed in the B/H pdfs as a small add on hoe for Ford skidsteer. Be simple to take a 3P/skidsteer hoe and add a power unit and make a small mobile B/H, remember this was in late 60s-70s. Small construction equipt was just coming online.

There are numerous pictures on the Net of small ARPS trenching machines. Some are just butt ugly, apparently worked well as ARPS survived thru numerous ownership changes. Some of the power units in those picture appear to use automotive parts, note the differentials have auto type hubcaps. Wonder if ARPS used auto sourced drive train parts. I love the names "Trench Devil"

I'm back to using the site plans to build a B/H. My efforts to purchase the non running/functioning ARPS unit have ended in failure.

Appreciate the comments
JLG

James Geraci