I'm still cogitating on exactly how I'm going to do it (soon). Maybe writing about it will help.
At Geneva steel the anchor bolts were cast into the concrete with flat plate welded to the bottom and cardboard tubes around them down about two feet (ten foot deep foundation).
The tubes were held up at the bottom by a nut and a big washer and at the top by another washer, then a nut then another washer and cardboard spacer about two inches long, then another washer, and then a steel plate about a foot square and an inch thick. The concrete was poured to within eight inches of the top and allowed to set. The machine (or more often a fabricated flat patterns) were set in place and leveled with the nuts below. Then grout was poured so that the mounting plates were barely 'proud'.
The above from a Millwright there for 32 years. The above was a 'standard' foundation for rolling stands and most were twelve feet wide and twenty long with twelve two inch diameter mounting bolts.
He says notice the machine is "supported by cardboard but held down by the mounting bolts." That means there's nearly two inches of 'take-up' room in each mounting bolt by crushing the cardboard of the cardboard spacer. That puts tension loading on a LOT of mounting bolt. He says DON'T mount a machine between two nuts on a threaded section of mounting bolt. It'll break between the nuts.
The grout handles the load and transmits it from the steel of the crankcase to the steel of the mounting plate to the grout and to the concrete foundation.
For my Lister, the platform will be 2x5 feet and 30 inches deep with a wider footprint at the bottom. It'll be poured insulated from the existing slab and will stand a foot higher than the surrounding floor. The top three inches will be grout.
I'll simplify the steel support pads used at Geneva with two parralel pieces of 3x6x1/2" angle iron frame suspended on eight 3/4" mounting bolts. The engine uses four and the frame for the genhead bolts uses the other four....or the whole unit could be reversed, or two engines mounted together....more options is also good. The spacing will be right for dual engines and enough drilled and tapped holes in the frame to accomodate most anything!
I'll weld a sheetmetal drip 'funnel' between the angles and weld in a spout that will be cast into the grout. Sounds like a GOOD plan to me!
It'll be easy to cast the bottom of the long angle iron legs about half in concrete and level and flatten the whole works with the adjustment nuts before it sets up. That means the steel portion of the mount is already stationary but it still hasn't taken a load before the final grouting to further stabalize it.
Then wait two weeks!!??