Go for it. I had many happy years with a CX and Palma with no troubles at all. Com star rear wheel can be converted to a car rim with a couple of steel polos quite easily. I didn't have a sub frame on mine, although it may have been the best option, just a steel plate bolted between the two lower engine eyes. Top mount was a long bolt with caps through the tube above the radiator on my 500, with an eye bolt on the end. Top rear was a tube clamp and the bottom rear was a plate mounted on the bolts rear of the rider foot rest. Watsonian supplied it all as a kit, although that was in the early 80's.
I made up a fork brace and some caps to allow me to put external springs over the fork tubes to stiffen the forks.