It's my impression, though i've been wrong before, that the Sprint engine lays over further to the passenger side of the car than the 1850, rather than the other way you suggested a few posts up. This simply from looking at the space an 1850 has for the exhaust manifold compared to a Sprint.
My thoughts were based on driving an 1850 that had been fitted with a sprint box and axle. The gearstick was leaning over to the passenger side. So my assumption is that the sprint would lay over over to the drivers side making the gearstick upright. I guess we will see!
The jag engine mounts are pretty thin, but reasonably compliant. They are a good design. And I thinkl the pair of mounting holes match the 1850 ones. Or are very very close.